CBOR Encoded X.509 Certificates (C509 Certificates)
draft-ietf-cose-cbor-encoded-cert-07
The information below is for an old version of the document.
| Document | Type |
This is an older version of an Internet-Draft whose latest revision state is "Active".
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|---|---|---|---|
| Authors | John Preuß Mattsson , Göran Selander , Shahid Raza , Joel Höglund , Martin Furuhed | ||
| Last updated | 2023-10-20 (Latest revision 2023-07-07) | ||
| Replaces | draft-mattsson-cose-cbor-cert-compress | ||
| RFC stream | Internet Engineering Task Force (IETF) | ||
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| Additional resources | Mailing list discussion | ||
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draft-ietf-cose-cbor-encoded-cert-07
Network Working Group J. Preuß Mattsson
Internet-Draft G. Selander
Intended status: Standards Track Ericsson AB
Expires: 22 April 2024 S. Raza
J. Höglund
RISE AB
M. Furuhed
Nexus Group
20 October 2023
CBOR Encoded X.509 Certificates (C509 Certificates)
draft-ietf-cose-cbor-encoded-cert-07
Abstract
This document specifies a CBOR encoding of X.509 certificates. The
resulting certificates are called C509 Certificates. The CBOR
encoding supports a large subset of RFC 5280 and all certificates
compatible with the RFC 7925, IEEE 802.1AR (DevID), CNSA, RPKI, GSMA
eUICC, and CA/Browser Forum Baseline Requirements profiles. When
used to re-encode DER encoded X.509 certificates, the CBOR encoding
can in many cases reduce the size of RFC 7925 profiled certificates
with over 50%. The CBOR encoded structure can alternatively be
signed directly ("natively signed"), which does not require re-
encoding for the signature to be verified. The document also
specifies C509 COSE headers, a C509 TLS certificate type, and a C509
file format.
About This Document
This note is to be removed before publishing as an RFC.
Status information for this document may be found at
https://datatracker.ietf.org/doc/draft-ietf-cose-cbor-encoded-cert/.
Discussion of this document takes place on the CBOR Object Signing
and Encryption Working Group mailing list (mailto:cose@ietf.org),
which is archived at https://mailarchive.ietf.org/arch/browse/cose/.
Subscribe at https://www.ietf.org/mailman/listinfo/cose/.
Source for this draft and an issue tracker can be found at
https://github.com/cose-wg/CBOR-certificates.
Status of This Memo
This Internet-Draft is submitted in full conformance with the
provisions of BCP 78 and BCP 79.
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Internet-Drafts are working documents of the Internet Engineering
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Internet-Drafts are draft documents valid for a maximum of six months
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This Internet-Draft will expire on 22 April 2024.
Copyright Notice
Copyright (c) 2023 IETF Trust and the persons identified as the
document authors. All rights reserved.
This document is subject to BCP 78 and the IETF Trust's Legal
Provisions Relating to IETF Documents (https://trustee.ietf.org/
license-info) in effect on the date of publication of this document.
Please review these documents carefully, as they describe your rights
and restrictions with respect to this document. Code Components
extracted from this document must include Revised BSD License text as
described in Section 4.e of the Trust Legal Provisions and are
provided without warranty as described in the Revised BSD License.
Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 3
2. Notational Conventions . . . . . . . . . . . . . . . . . . . 5
3. C509 Certificate . . . . . . . . . . . . . . . . . . . . . . 5
3.1. Message Fields . . . . . . . . . . . . . . . . . . . . . 5
3.2. Encoding of subjectPublicKey and issuerSignatureValue . . 9
3.3. Encoding of Extensions . . . . . . . . . . . . . . . . . 10
3.4. COSE Header Parameters . . . . . . . . . . . . . . . . . 15
4. C509 Certificate Signing Request . . . . . . . . . . . . . . 16
5. C509 Processing and Certificate Issuance . . . . . . . . . . 17
6. Legacy Considerations . . . . . . . . . . . . . . . . . . . . 18
7. Expected Certificate Sizes . . . . . . . . . . . . . . . . . 19
8. Security Considerations . . . . . . . . . . . . . . . . . . . 20
9. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 20
9.1. C509 Certificate Types Registry . . . . . . . . . . . . . 21
9.2. C509 Attributes Registry . . . . . . . . . . . . . . . . 21
9.3. C509 Extensions Registry . . . . . . . . . . . . . . . . 25
9.4. C509 Certificate Policies Registry . . . . . . . . . . . 30
9.5. C509 Policies Qualifiers Registry . . . . . . . . . . . . 32
9.6. C509 Information Access Registry . . . . . . . . . . . . 33
9.7. C509 Extended Key Usages Registry . . . . . . . . . . . . 35
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9.8. C509 General Names Registry . . . . . . . . . . . . . . . 37
9.9. C509 Signature Algorithms Registry . . . . . . . . . . . 38
9.10. C509 Public Key Algorithms Registry . . . . . . . . . . . 42
9.11. COSE Header Parameters Registry . . . . . . . . . . . . . 46
9.12. Media Type application/cose-c509 . . . . . . . . . . . . 46
9.13. TLS Certificate Types Registry . . . . . . . . . . . . . 47
9.14. CBOR Tags Registry . . . . . . . . . . . . . . . . . . . 47
10. References . . . . . . . . . . . . . . . . . . . . . . . . . 47
10.1. Normative References . . . . . . . . . . . . . . . . . . 47
10.2. Informative References . . . . . . . . . . . . . . . . . 49
Appendix A. Example C509 Certificates . . . . . . . . . . . . . 52
A.1. Example RFC 7925 profiled X.509 Certificate . . . . . . . 52
A.2. Example IEEE 802.1AR profiled X.509 Certificate . . . . . 56
A.3. Example CAB Baseline ECDSA HTTPS X.509 Certificate . . . 56
A.4. Example CAB Baseline RSA HTTPS X.509 Certificate . . . . 58
Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . . . 61
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 62
1. Introduction
One of the challenges with deploying a Public Key Infrastructure
(PKI) for the Internet of Things (IoT) is the size and parsing of
X.509 public key certificates [RFC5280], since those are not
optimized for constrained environments [RFC7228]. Large certificate
chains are also problematic in non-constrained protocols such as EAP-
TLS [RFC9190] [RFC9191] where authenticators typically drop an EAP
session after only 40 - 50 round-trips, QUIC [RFC9000] where the
latency increases significantly unless the server sends less than
three times as many bytes as received prior to validating the client
address, and RPKI [RFC6487] where a single certificate can be very
large. More compact certificate representations are therefore
desirable in many use cases. Due to the current PKI usage of DER
encoded X.509 certificates, keeping compatibility with DER encoded
X.509 is necessary at least for a transition period. However, the
use of a more compact encoding with the Concise Binary Object
Representation (CBOR) [RFC8949] reduces the certificate size
significantly which has known performance benefits in terms of
decreased communication overhead, power consumption, latency,
storage, etc.
CBOR is a data format designed for small code size and small message
size. CBOR builds on the JSON data model but extends it by e.g.
encoding binary data directly without base64 conversion. In addition
to the binary CBOR encoding, CBOR also has a diagnostic notation that
is readable and editable by humans. The Concise Data Definition
Language (CDDL) [RFC8610] provides a way to express structures for
protocol messages and APIs that use CBOR. RFC 8610 also extends the
diagnostic notation.
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CBOR data items are encoded to or decoded from byte strings using a
type-length-value encoding scheme, where the three highest order bits
of the initial byte contain information about the major type. CBOR
supports several different types of data items, in addition to
integers (int, uint), simple values (e.g. null), byte strings (bstr),
and text strings (tstr), CBOR also supports arrays [] of data items,
maps {} of pairs of data items, and sequences of data items. For a
complete specification and examples, see [RFC8949], [RFC8610], and
[RFC8742]. We recommend implementors to get used to CBOR by using
the CBOR playground [CborMe].
CAB Baseline Requirements [CAB-TLS], RFC 7925 [RFC7925], IEEE 802.1AR
[IEEE-802.1AR], and CNSA [RFC8603] specify certificate profiles which
can be applied to certificate based authentication with, e.g., TLS
[RFC8446], QUIC [RFC9000], DTLS [RFC9147], COSE [RFC9052], EDHOC
[I-D.ietf-lake-edhoc], or Compact TLS 1.3 [I-D.ietf-tls-ctls]. RFC
7925 [RFC7925], RFC7925bis [I-D.ietf-uta-tls13-iot-profile], and IEEE
802.1AR [IEEE-802.1AR] specifically target Internet of Things
deployments. This document specifies a CBOR encoding based on
[X.509-IoT], which can support large parts of RFC 5280. The encoding
supports all RFC 7925, IEEE 802.1AR, CAB Baseline [CAB-TLS],
[CAB-Code], RPKI [RFC6487], eUICC [GSMA-eUICC] profiled X.509
certificates. The resulting certificates are called C509
Certificates. This document does not specify a certificate profile.
Two variants are defined using the same CBOR encoding and differing
only in what is being signed:
1. An invertible CBOR re-encoding of DER encoded X.509 certificates
[RFC5280], which can be reversed to obtain the original DER
encoded X.509 certificate.
2. Natively signed C509 certificates, where the signature is
calculated over the CBOR encoding instead of over the DER
encoding as in 1. This removes the need for ASN.1 and DER
parsing and the associated complexity but they are not backwards
compatible with implementations requiring DER encoded X.509.
Natively signed C509 certificates can be applied in devices that are
only required to authenticate to natively signed C509 certificate
compatible servers, which is not a major restriction for many IoT
deployments where the parties issuing and verifying certificates can
be a restricted ecosystem.
This document specifies COSE headers for use of the C509 certificates
with COSE, see Section 9.11. The document also specifies a TLS
certificate type for use of the C509 certificates with TLS and QUIC
(with or without additional TLS certificate compression), see
Section 9.13.
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2. Notational Conventions
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and
"OPTIONAL" in this document are to be interpreted as described in BCP
14 [RFC2119] [RFC8174] when, and only when, they appear in all
capitals, as shown here.
This specification makes use of the terminology in [RFC5280],
[RFC7228], [RFC8610], and [RFC8949]. When referring to CBOR, this
specification always refers to Deterministically Encoded CBOR as
specified in Sections 4.2.1 and 4.2.2 of [RFC8949].
3. C509 Certificate
This section specifies the content and encoding for C509
certificates, with the overall objective to produce a very compact
representation supporting large parts of [RFC5280], and everything in
[RFC7925], [IEEE-802.1AR], RPKI [RFC6487], GSMA eUICC [GSMA-eUICC],
and CAB Baseline [CAB-TLS] [CAB-Code]. In the CBOR encoding, static
fields are elided, elliptic curve points and time values are
compressed, OID are replaced with short integers, and redundant
encoding is removed. Combining these different components reduces
the certificate size significantly, which is not possible with
general purpose compression algorithms, see Figure 4.
The C509 certificate can be either a CBOR re-encoding of a DER
encoded X.509 certificate, in which case the signature is calculated
on the DER encoded ASN.1 data in the X.509 certificate, or a natively
signed C509 certificate, in which case the signature is calculated
directly on the CBOR encoded data. In both cases the certificate
content is adhering to the restrictions given by [RFC5280]. The re-
encoding is known to work with DER encoded certificates but might
work with other canonical encodings. The re-encoding does not work
for BER encoded certificates.
In the encoding described below, the order of elements in arrays are
always encoded in the same order as the elements or the corresponding
SEQUENCE or SET in the DER encoding.
3.1. Message Fields
The X.509 fields and their CBOR encodings are listed below, and used
in the definition of C509 certificates, see Figure 1.
C509 certificates are defined in terms of DER encoded [RFC5280] X.509
certificates:
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* version. The 'version' field is encoded in the
'c509CertificateType' CBOR int. The field 'c509CertificateType'
also indicates the type of the C509 certificate. Currently, the
type can be a natively signed C509 certificate following X.509 v3
(c509CertificateType = 0) or a CBOR re-encoded X.509 v3 DER
certificate (c509CertificateType = 1), see Section 9.1.
* serialNumber. The 'serialNumber' INTEGER value field is encoded
as the unwrapped CBOR unsigned bignum (~biguint)
'certificateSerialNumber'. Any leading 0x00 byte (to indicate
that the number is not negative) is therefore omitted.
* signature. The 'signature' field is always the same as the
'signatureAlgorithm' field and therefore omitted from the CBOR
encoding.
* issuer. In the general case, the sequence of
'RelativeDistinguishedName' is encoded as a CBOR array of CBOR
arrays of Attributes. Typically, each RelativeDistinguishedName
only contains a single attribute and the sequence is then encoded
as a CBOR array of Attributes. Each Attribute is encoded as a
(CBOR int, CBOR text string) pair or as a (unwrapped CBOR OID,
CBOR bytes) pair. The absolute value of the CBOR int (see
Figure 6) encodes the attribute type and the sign is used to
represent the character string type; positive for Utf8String,
negative for PrintableString. The Attribute Email Address is
always an IA5String. In natively signed C509 certificates all
text strings are UTF-8 encoded and all attributeType SHALL be non-
negative. Text strings SHALL still adhere to any X.509
restrictions, i.e., serialNumber SHALL only contain the 74
character subset of ASCII allowed by PrintableString and
countryName SHALL have length 2. The string types teletexString,
universalString, and bmpString are not supported. If Name
contains a single Attribute containing an utf8String encoded
'common name' it is encoded as follows:
- If the text string contains only the symbols '0'–'9' or
'a'–'f', it is encoded as a CBOR byte string, prefixed with an
initial byte set to '00'.
- If the text string contains an EUI-64 of the form "HH-HH-HH-HH-
HH-HH-HH-HH" where 'H' is one of the symbols '0'–'9' or 'A'–'F'
it is encoded as a CBOR byte string prefixed with an initial
byte set to '01', for a total length of 9. An EUI-64 mapped
from a 48-bit MAC address (i.e., of the form "HH-HH-HH-FF-FE-
HH-HH-HH) is encoded as a CBOR byte string prefixed with an
initial byte set to '01', for a total length of 7.
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- Otherwise it is encoded as a CBOR text string.
* validity. The 'notBefore' and 'notAfter' fields are encoded as
unwrapped CBOR epoch-based date/time (~time) where the tag content
is an unsigned integer. In POSIX time, leap seconds are ignored,
with a leap second having the same POSIX time as the second before
it. Compression of X.509 certificates with the time 23:59:60 UTC
is therefore not supported. Note that RFC 5280 mandates encoding
of dates through the year 2049 as UTCTime, and later dates as
GeneralizedTime. The value "99991231235959Z" (no expiration date)
is encoded as CBOR null.
* subject. The 'subject' is encoded exactly like issuer.
* subjectPublicKeyInfo. The 'AlgorithmIdentifier' field including
parameters is encoded as the CBOR int 'subjectPublicKeyAlgorithm'
(see Section 9.10) or as an array with an unwrapped CBOR OID tag
[RFC9090] optionally followed by the parameters encoded as a CBOR
byte string. In general, the 'subjectPublicKey' BIT STRING value
field is encoded as a CBOR byte string. This specification
assumes the BIT STRING has zero unused bits and the unused bits
byte is omitted. For rsaEncryption and id-ecPublicKey, the
encoding of subjectPublicKey is further optimized as described in
Section 3.2.
* issuerUniqueID. Not supported.
* subjectUniqueID. Not supported.
* extensions. The 'extensions' field is encoded as a CBOR array
where each extension is encoded as either a CBOR int (see
Section 9.3) followed by an optional CBOR item of any type or an
unwrapped CBOR OID tag [RFC9090] followed by a CBOR bool encoding
'critical' and the DER encoded value of the 'extnValue' encoded as
a CBOR byte string. If the array contains exactly two ints and
the absolute value of the first int is 2 (corresponding to
keyUsage), the array is omitted and the extensions is encoded as a
single CBOR int with the absolute value of the second int and the
sign of the first int. Extensions are encoded as specified in
Section 3.3. The extensions mandated to be supported by [RFC7925]
and [IEEE-802.1AR] are given special treatment. An omitted
'extensions' field is encoded as an empty CBOR array.
* signatureAlgorithm. The 'signatureAlgorithm' field including
parameters is encoded as a CBOR int (see Section 9.9) or as an
array with an unwrapped CBOR OID tag [RFC9090] optionally followed
by the parameters encoded as a CBOR byte string.
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* signatureValue. In general, the 'signatureValue' BIT STRING value
field is encoded as the CBOR byte string issuerSignatureValue.
This specification assumes the BIT STRING has zero unused bits and
the unused bits byte is omitted. For natively signed C509
certificates the signatureValue is calculated over the CBOR
sequence TBSCertificate. For ECDSA, the encoding of
issuerSignatureValue is further optimized as described in
Section 3.2
The following Concise Data Definition Language (CDDL) defines the
CBOR array C509Certificate and the CBOR sequence [RFC8742]
TBSCertificate. The member names therefore only have documentary
value. Applications not requiring a CBOR item MAY represent C509
certificates with the CBOR sequence ~C509Certificate (unwrapped
C509Certificate).
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C509Certificate = [
TBSCertificate,
issuerSignatureValue : any,
]
; The elements of the following group are used in a CBOR Sequence:
TBSCertificate = (
c509CertificateType: int,
certificateSerialNumber: CertificateSerialNumber,
issuer: Name,
validityNotBefore: Time,
validityNotAfter: Time,
subject: Name,
subjectPublicKeyAlgorithm: AlgorithmIdentifier,
subjectPublicKey: any,
extensions: Extensions,
issuerSignatureAlgorithm: AlgorithmIdentifier,
)
CertificateSerialNumber = ~biguint
Name = [ * RelativeDistinguishedName ] / text / bytes
RelativeDistinguishedName = Attribute / [ 2* Attribute ]
Attribute = ( attributeType: int, attributeValue: text ) //
( attributeType: ~oid, attributeValue: bytes )
Time = ~time / null
AlgorithmIdentifier = int / ~oid /
[ algorithm: ~oid, parameters: bytes ]
Extensions = [ * Extension ] / int
Extension = ( extensionID: int, extensionValue: any ) //
( extensionID: ~oid, ? critical: true,
extensionValue: bytes )
Figure 1: CDDL for C509Certificate.
3.2. Encoding of subjectPublicKey and issuerSignatureValue
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3.2.1. Encoding of subjectPublicKey
For RSA public keys (rsaEncryption), the SEQUENCE and INTEGER type
and length fields are omitted and the two INTEGER value fields
(modulus, exponent) are encoded as an array of two unwrapped CBOR
unsigned bignum (~biguint), i.e. [ modulus : ~biguint, exponent :
~biguint ]. If the exponent is 65537, the array and the exponent is
omitted and subjectPublicKey consist of only the modulus encoded as
an unwrapped CBOR unsigned bignum (~biguint).
For elliptic curve public keys in Weierstraß form (id-ecPublicKey),
keys may be point compressed as defined in Section 2.3.3 of [SECG].
Native C509 certificates with Weierstraß form keys use the octets
0x02, 0x03, and 0x04 as defined in [SECG]. If a DER encoded
certificate with a uncompressed public key of type id-ecPublicKey is
CBOR encoded with point compression, the octets 0xfe and 0xfd are
used instead of 0x02 and 0x03 in the CBOR encoding to represent even
and odd y-coordinate, respectively.
3.2.2. Encoding of issuerSignatureValue
For ECDSA signatures, the SEQUENCE and INTEGER type and length fields
as well as the any leading 0x00 byte (to indicate that the number is
not negative) are omitted. If the two INTEGER value fields have
different lengths, the shorter INTEGER value field is padded with
zeroes so that the two fields have the same length. The resulting
byte string is encoded as a CBOR byte string.
3.3. Encoding of Extensions
This section details the encoding of the 'extensions' field. The
'extensions' field is encoded as a CBOR array where each extensionID
is encoded either as a CBOR int or as an unwrapped CBOR OID tag. If
'extensionID' is encoded an int (see Section 9.3), the sign is used
to encode if the extension is critical and the 'critical' field is
omitted. Critical extensions are encoded with a negative sign and
non-critical extensions are encoded with a positive sign.
The 'extnValue' OCTET STRING value field is encoded as the CBOR byte
string 'extensionValue' except for the extensions specified below.
For some extensions, only commonly used parts are supported by the
CBOR encoding. If unsupported parts are used, the CBOR encoding
cannot be used.
CBOR encoding of the following extension values are fully supported:
* Subject Key Identifier (subjectKeyIdentifier). The extensionValue
is encoded as follows:
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KeyIdentifier = bytes
SubjectKeyIdentifier = KeyIdentifier
* Key Usage (keyUsage). The 'KeyUsage' BIT STRING is interpreted as
an unsigned integer in network byte order and encoded as a CBOR
int. See Section 3.1 for special encoding in case keyUsage is the
only extension present.
KeyUsage = int
* Policy Mappings (policyMappings). extensionValue is encoded as
follows:
PolicyMappings = [
+ (issuerDomainPolicy: ~oid, subjectDomainPolicy: ~oid)
]
* Basic Constraints (basicConstraints). If 'cA' = false then
extensionValue = -2, if 'cA' = true and 'pathLenConstraint' is not
present then extensionValue = -1, and if 'cA' = true and
'pathLenConstraint' is present then extensionValue =
pathLenConstraint.
BasicConstraints = int
* Policy Constraints (policyConstraints). extensionValue is encoded
as follows:
PolicyConstraints = [
requireExplicitPolicy: uint / null,
inhibitPolicyMapping: uint / null,
]
* Extended Key Usage (extKeyUsage). extensionValue is encoded as an
array of CBOR ints (see Section 9.7 or unwrapped CBOR OID tags
[RFC9090] where each int or OID tag encodes a key usage purpose.
If the array contains a single KeyPurposeId, the array is omitted.
KeyPurposeId = int / ~oid
ExtKeyUsageSyntax = [ 2* KeyPurposeId ] / KeyPurposeId
* Inhibit anyPolicy (inhibitAnyPolicy). extensionValue is encoded as
follows:
InhibitAnyPolicy = uint
CBOR encoding of the following extension values are partly supported:
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* Subject Alternative Name (subjectAltName). If the subject
alternative name only contains general names registered in
Section 9.8 the extension value can be CBOR encoded.
extensionValue is encoded as an array of (int, any) pairs where
each pair encodes a general name (see Section 9.8). If
subjectAltName contains exactly one dNSName, the array and the int
are omitted and extensionValue is the dNSName encoded as a CBOR
text string. In addition to the general names defined in
[RFC5280], the hardwareModuleName type of otherName has been given
its own int due to its mandatory use in IEEE 802.1AR. When
'otherName + hardwareModuleName' is used, then [ oid, bytes ] is
used to identify the pair ( hwType, hwSerialEntries ) directly as
specified in [RFC4108]. Only the general names in Section 9.8 are
supported.
GeneralName = ( GeneralNameType : int, GeneralNameValue : any )
GeneralNames = [ + GeneralName ]
SubjectAltName = GeneralNames / text
* Issuer Alternative Name (issuerAltName). extensionValue is encoded
exactly like subjectAltName.
IssuerAltName = GeneralNames / text
* CRL Distribution Points (cRLDistributionPoints). If the CRL
Distribution Points is a sequence of DistributionPointName, where
each DistributionPointName only contains
uniformResourceIdentifiers, the extension value can be CBOR
encoded. extensionValue is encoded as follows:
DistributionPointName = [ 2* text ] / text
CRLDistributionPoints = [ + DistributionPointName ]
* Freshest CRL (freshestCRL). extensionValue is encoded exactly like
cRLDistributionPoints.
FreshestCRL = CRLDistributionPoints
* Authority Information Access (authorityInfoAccess). If all the
GeneralNames in authorityInfoAccess are of type
uniformResourceIdentifier, the extension value can be CBOR
encoded. Each accessMethod is encoded as a CBOR int (see
Section 9.6) or an unwrapped CBOR OID tag [RFC9090]. The
uniformResourceIdentifiers are encoded as CBOR text strings.
AccessDescription = ( accessMethod: int / ~oid , uri: text )
AuthorityInfoAccessSyntax = [ + AccessDescription ]
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* Subject Information Access (subjectInfoAccess). Encoded exactly
like authorityInfoAccess.
SubjectInfoAccessSyntax = AuthorityInfoAccessSyntax
* Authority Key Identifier (authorityKeyIdentifier). If the
authority key identifier contains all of keyIdentifier,
certIssuer, and certSerialNumberm or if only keyIdentifier is
present the extension value can be CBOR encoded. If all three are
present a CBOR array is used, if only keyIdentifier is present,
the array is omitted:
KeyIdentifierArray = [
keyIdentifier: KeyIdentifier / null,
authorityCertIssuer: GeneralNames,
authorityCertSerialNumber: CertificateSerialNumber
]
AuthorityKeyIdentifier = KeyIdentifierArray / KeyIdentifier
* Certificate Policies (certificatePolicies). If noticeRef is not
used and any explicitText are encoded as UTF8String, the extension
value can be CBOR encoded. OIDs registered in Section 9.4 are
encoded as an int. The policyQualifierId is encoded as an CBOR
int (see Section 9.5) or an unwrapped CBOR OID tag [RFC9090].
PolicyIdentifier = int / ~oid
PolicyQualifierInfo = (
policyQualifierId: int / ~oid,
qualifier: text,
)
CertificatePolicies = [
+ ( PolicyIdentifier, ? [ + PolicyQualifierInfo ] )
]
* Name Constraints (nameConstraints). If the name constraints only
contains general names registered in Section 9.8 the extension
value can be CBOR encoded. Note that [RFC5280] requires that
minimum MUST be zero, and maximum MUST be absent.
GeneralSubtree = [ GeneralName ]
NameConstraints = [
permittedSubtrees: GeneralSubtree / null,
excludedSubtrees: GeneralSubtree / null,
]
* Subject Directory Attributes (subjectDirectoryAttributes).
Encoded as attributes in issuer and subject with the difference
that there can be more than one attributeValue.
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Attributes = ( attributeType: int, attributeValue: [+text] ) //
( attributeType: ~oid, attributeValue: [+bytes] )
SubjectDirectoryAttributes = [+Attributes]
* AS Resources (autonomousSysIds). If rdi is not present, the
extension value can be CBOR encoded. Each ASId is encoded as an
uint. With the exception of the first ASId, the ASid is encoded
as the difference to the previous ASid.
AsIdsOrRanges = uint / [uint, uint]
ASIdentifiers = [ + AsIdsOrRanges ] / null
* AS Resources v2 (autonomousSysIds-v2). Encoded exactly like
autonomousSysIds.
* IP Resources (id-pe-ipAddrBlocks). If rdi and SAFI is not
present, the extension value can be CBOR encoded. Each
AddressPrefix is encoded as a CBOR bytes string (without the
unused bits octet) followed by the number of unused bits encoded
as a CBOR uint. Each AddressRange is encoded as an array of two
CBOR byte strings. The unused bits for min and max are omitted,
but the unused bits in max IPAddress is set to ones. With the
exception of the first Address, if the byte string has the same
length as the previous Address, the Address is encoded as an uint
with the the difference to the previous Address. It should be
noted that using address differences for compactness prevents
encoding an address range larger than 2^64 - 1 corresponding to
the cbor integer max value.
Address = bytes / uint,
AddressPrefix = (Address, unusedBits: uint)
AddressRange = [Address, Address]
IPAddressOrRange = AddressPrefix / AddressRange
IPAddressChoice = [ + IPAddressOrRange ] / null
IPAddrBlocks = [ AFI: uint, IPAddressChoice ]
* IP Resources v2 (id-pe-ipAddrBlocks-v2). Encoded exactly like id-
pe-ipAddrBlocks.
* Signed Certificate Timestamp. If all the SCTs are version 1, and
there are no SCT extensions, the extension value can be CBOR
encoded. LogIDs are encoded as CBOR byte strings, the timestamp
is encoded as a CBOR int (milliseconds since validityNotBefore),
and the signature is encoded with an (AlgorithmIdentifier, any)
pair in the same way as issuerSignatureAlgorithm and
issuerSignatureValue.
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SignedCerticateTimestamp = (
logID: bytes,
timestamp: int,
sigAlg: AlgorithmIdentifier,
sigValue: any,
)
SignedCertificateTimestamps = [ + SignedCerticateTimestamp ]
3.3.1. Example Encoding of Extensions
The examples below use values from Section 9.3, Section 9.7, and
Section 9.8:
* A critical basicConstraints ('cA' = true) without
pathLenConstraint is encoded as the two CBOR ints -4, -1.
* A non-critical keyUsage with digitalSignature and keyAgreement
asserted is encoded as the two CBOR ints 2, 17 (2^0 + 2^4 = 17).
* A non-critical extKeyUsage containing id-kp-codeSigning and id-kp-
OCSPSigning is encoded as the CBOR int 8 followed by the CBOR
array [ 3, 6 ].
* A non-critical subjectAltName containing only the dNSName
example.com is encoded as the CBOR int 3 followed by the CBOR text
string "example.com".
Thus, the extension field of a certificate containing all of the
above extensions in the given order would be encoded as the CBOR
array [ -4, -1, 2, 17, 8, [ 3, 6 ], 3, "example.com" ].
3.4. COSE Header Parameters
The formatting and processing for c5b, c5c, and c5t, and c5u, defined
in Table 1 are similar to x5bag, x5chain, x5t, x5u defined in
[RFC9360] except that the certificates are C509 instead of DER
encoded X.509 and uses a COSE_C509 structure instead of COSE_X509.
c5u provides an alternative way to identify an untrusted certificate
bag/chain by reference with a URI. The content is a COSE_C509 item
served with the application/cose-c509 content format. The COSE_C509
structure used in c5b, c5c, and c5u is defined as:
COSE_C509 = C509Certificate / [ 2* C509Certificate ]
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As the contents of c5b, c5c, c5t, and c5u are untrusted input, the
header parameters can be in either the protected or unprotected
header bucket. The trust mechanism MUST process any certificates in
the c5b, c5c, and c5u parameters as untrusted input. The presence of
a self-signed certificate in the parameter MUST NOT cause the update
of the set of trust anchors without some out-of-band confirmation.
+======+=======+===============+=============================+
| Name | Label | Value Type | Description |
+======+=======+===============+=============================+
| c5b | TBD1 | COSE_C509 | An unordered bag of C509 |
| | | | certificates |
+------+-------+---------------+-----------------------------+
| c5c | TBD2 | COSE_C509 | An ordered chain of C509 |
| | | | certificates |
+------+-------+---------------+-----------------------------+
| c5t | TBD3 | COSE_CertHash | Hash of a C509Certificate |
+------+-------+---------------+-----------------------------+
| c5u | TBD4 | uri | URI pointing to a COSE_C509 |
| | | | containing a ordered chain |
| | | | of certificates |
+------+-------+---------------+-----------------------------+
Table 1: COSE Header Parameters
Note that certificates can also be identified with a 'kid' header
parameter by storing 'kid' and the associated bag or chain in a
dictionary.
4. C509 Certificate Signing Request
The section defines the format of a C509 Certificate Signing Request
(CSR), also known as a C509 Certificate Request, based on and
compatible with RFC 2986 [RFC2986] reusing the formatting for C509
certificates defined in Section 3. There are currently two
c509CertificateRequestType values defined, c509CertificateRequestType
= 0 requests a c509CertificateType = 0 and c509CertificateRequestType
= 1 requests a c509CertificateType = 1. subjectSignatureAlgorithm can
be a signature algorithm or a non-signature proof-of-possession
algorithm, e.g. as defined in [RFC6955]. In the latter case, the
signature is replaced by a MAC and requires a public Diffie-Hellman
key of the verifier distributed out-of-band. Both kinds are listed
in the C509 Signature Algorithms Registry, see Section 9.9.
Certificate request attributes, i.e. attributes for use with
certificate requests providing additional information about the
subject of the certificate, are defined in Section 5.4 of [RFC2985].
The attribute extensionRequest is supported with a dedicated element.
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Other certificate request attributes are included using the same
Extensions structure as in extensionsRequest, both extensions and
attributes are listed in the C509 Extensions Registry, see Figure 7.
The only other certificate request attribute specified in this
document is challengePassword which is defined for utf8String values
and encoded as CBOR text string, except if the text string contains
only the symbols '0'–'9' or 'a'–'f', in which case it is encoded as a
CBOR byte string.
C509CertificateRequest = [
TBSCertificateRequest,
subjectSignatureValue: any,
]
; The elements of the following group are used in a CBOR Sequence:
TBSCertificateRequest = (
c509CertificateRequestType: int,
subject: Name,
subjectPublicKeyAlgorithm: AlgorithmIdentifier,
subjectPublicKey: any,
extensionsRequest: Extensions,
subjectSignatureAlgorithm: AlgorithmIdentifier,
)
challengePassword: tstr / bstr
Figure 2: CDDL for C509CertificateRequest.
After verifying the subjectSignatureValue, the CA MAY transform the
C509CertificateRequest into a [RFC2986] CertificationRequestInfo for
compatibility with existing procedures and code.
5. C509 Processing and Certificate Issuance
It is straightforward to integrate the C509 format into legacy X.509
processing during certificate issuance. C509 processing can be
performed as an isolated function of the CA, or as a separate
function trusted by the CA.
The Certificate Signing Request (CSR)) format defined in Section 4
follows the PKCS#10 format to enable a direct mapping to the
certification request information, see Section 4.1 of [RFC2986].
When a certificate request is received the CA, or function trusted by
the CA, needs to perform some limited C509 processing and verify the
proof-of-possession of the public key, before normal certificate
generation can take place.
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In the reverse direction, in case c509CertificateType = 1 was
requested, a separate C509 processing function can perform the
conversion from a generated X.509 certificate to C509 as a bump-in-
the-wire. In case c509CertificateType = 0 was requested, the C509
processing needs to be performed before signing the certificate, in
which case a tighter integration with CA may be needed.
6. Legacy Considerations
C509 certificates can be deployed with legacy X.509 certificates and
CA infrastructure. An existing CA can continue to use its existing
procedures and code for PKCS#10, and DER encoded X.509 and only
implement C509 as a thin processing layer on top. When receiving a
C509 CSR, the CA transforms it into a DER encoded RFC 2986
CertificationRequestInfo and use that with existing processes and
code to produce an RFC 5280 DER encoded X.509 certificate. The DER
encoded X509 is then transformed into a C509 certificate. At any
later point, the C509 certificate can be used to recreate the
original X.509 data structure needed to verify the signature.
For protocols like TLS/DTLS 1.2, where the handshake is sent
unencrypted, the actual encoding and compression can be done at
different locations depending on the deployment setting. For
example, the mapping between C509 certificate and standard X.509
certificate can take place in a 6LoWPAN border gateway which allows
the server side to stay unmodified. This case gives the advantage of
the low overhead of a C509 certificate over a constrained wireless
links. The conversion to X.509 within an IoT device will incur a
computational overhead, however, measured in energy this is likely to
be negligible compared to the reduced communication overhead.
For the setting with constrained server and server-only
authentication, the server only needs to be provisioned with the C509
certificate and does not perform the conversion to X.509. This
option is viable when client authentication can be asserted by other
means.
For protocols like IKEv2, TLS/DTLS 1.3, and EDHOC, where certificates
are encrypted, the proposed encoding needs to be done fully end-to-
end, through adding the encoding/decoding functionality to the
server.
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7. Expected Certificate Sizes
The CBOR encoding of the sample certificate chains given in
Appendix A results in the numbers shown in Figure 3 and Figure 4.
COSE_X509 is defined in [RFC9360] and COSE_C509 is defined in
Section 9.11. After RFC 7925 profiling, most duplicated information
has been removed, and the remaining text strings are minimal in size.
Therefore, the further size reduction reached with general
compression mechanisms such as Brotli will be small, mainly
corresponding to making the ASN.1 encoding more compact. CBOR
encoding can however significantly compress RFC 7925 profiled
certificates. For the example HTTPS certificate chains (www.ietf.org
and tools.ietf.org) both C509 and Brotli perform well complementing
each other. C509 use dedicated information to compress individual
certificates, while Brotli can compress duplicate information in the
entire chain. Note that C509 certificates of type 0 and 1 have the
same size. For Brotli [RFC7932], the Rust crate Brotli 3.3.0 was
used with compression level 11 and window size 22.
+---------------------------------------+-----------+-----------+
| | COSE_X509 | COSE_C509 |
+---------------------------------------+-----------+-----------+
| RFC 7925 profiled IoT Certificate (1) | 317 | 139 |
+---------------------------------------+-----------+-----------+
| ECDSA HTTPS Certificate Chain (2) | 2193 | 1394 |
+---------------------------------------+-----------+-----------+
| RSA HTTPS Certificate Chain (4) | 5175 | 3934 |
+---------------------------------------+-----------+-----------+
Figure 3: Comparing Sizes of Certificate Chains in COSE. Number
of bytes (length of certificate chain).
+-------------------+-------+---------------+------+---------------+
| | X509 | X509 + Brotli | C509 | C509 + Brotli |
+-------------------+-------+---------------+------+---------------+
| RFC 7925 Cert (1) | 327 | 324 | 151 | 167 |
+-------------------+-------+---------------+------+---------------+
| RPKI Cert (1) | 20991 | 9134 | 8660 | 5668 |
+-------------------+-------+---------------+------+---------------+
| HTTPS Chain (2) | 2204 | 1455 | 1414 | 1063 |
+-------------------+-------+---------------+------+---------------+
| HTTPS Chain (4) | 5190 | 3244 | 3958 | 2845 |
+-------------------+-------+---------------+------+---------------+
| HTTPS Bag (8) | 11578 | 3979 | 8882 | 3519 |
+-------------------+-------+---------------+------+---------------+
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Figure 4: Comparing Sizes of Certificate Chains with TLS. Number
of bytes (length of certificate chain). X509 and C509 are
Certificate messages. X509 + Brotli and C509 + Brotli are
CompressedCertificate messages.
8. Security Considerations
The CBOR profiling of X.509 certificates does not change the security
assumptions needed when deploying standard X.509 certificates but
decreases the number of fields transmitted, which reduces the risk
for implementation errors.
The use of natively signed C509 certificates removes the need for
ASN.1 encoding, which is a rich source of security vulnerabilities.
Conversion between the certificate formats can be made in constant
time to reduce risk of information leakage through side channels.
The mechanism in this draft does not reveal any additional
information compared to X.509. Because of difference in size, it
will be possible to detect that this profile is used. The gateway
solution described in Section 6 requires unencrypted certificates and
is not recommended.
9. IANA Considerations
This document creates several new registries under the new heading
"C509 Certificate". For all items, the 'Reference' field points to
this document.
The expert reviewers for the registries defined in this document are
expected to ensure that the usage solves a valid use case that could
not be solved better in a different way, that it is not going to
duplicate one that is already registered, and that the registered
point is likely to be used in deployments. They are furthermore
expected to check the clarity of purpose and use of the requested
code points. Experts should take into account the expected usage of
entries when approving point assignment, and the length of the
encoded value should be weighed against the number of code points
left that encode to that size and how constrained the systems it will
be used on are. Values in the interval [-24, 23] have a 1 byte
encodings, other values in the interval [-256, 255] have a 2 byte
encodings, and the remaining values in the interval [-65536, 65535]
have 3 byte encodings.
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9.1. C509 Certificate Types Registry
IANA has created a new registry titled "C509 Certificate Types" under
the new heading "C509 Certificate". The columns of the registry are
Value, Description, and Reference, where Value is an integer, and the
other columns are text strings. For values in the interval [-24, 23]
the registration procedure is "IETF Review" and "Expert Review". For
all other values the registration procedure is "Expert Review". The
initial contents of the registry are:
+-------+-----------------------------------------------------------+
| Value | Description |
+=======+===========================================================+
| 0 | Natively Signed C509 Certificate following X.509 v3 |
+-------+-----------------------------------------------------------+
| 1 | CBOR re-encoding of X.509 v3 Certificate |
+-------+-----------------------------------------------------------+
Figure 5: C509 Certificate Types
9.2. C509 Attributes Registry
IANA has created a new registry titled "C509 Attributes" under the
new heading "CBOR Encoded X509 Certificates (C509 Certificates)".
The columns of the registry are Value, Name, Identifiers, OID, DER,
Comments, and Reference, where Value is an non-negative integer, and
the other columns are text strings. For values in the interval [0,
23] the registration procedure is "IETF Review" and "Expert Review".
For all other values the registration procedure is "Expert Review".
The initial contents of the registry are:
+-------+-----------------------------------------------------------+
| Value | Attribute |
+=======+===========================================================+
| 0 | Name: Email Address |
| | Identifiers: emailAddress, e-mailAddress |
| | OID: 1.2.840.113549.1.9.1 |
| | DER: 06 09 2A 86 48 86 F7 0D 01 09 01 |
| | Comments: |
+-------+-----------------------------------------------------------+
| 1 | Name: Common Name |
| | Identifiers: commonName, cn |
| | OID: 2.5.4.3 |
| | DER: 06 03 55 04 03 |
| | Comments: |
+-------+-----------------------------------------------------------+
| 2 | Name: Surname |
| | Identifiers: surname, sn |
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| | OID: 2.5.4.4 |
| | DER: 06 03 55 04 04 |
| | Comments: |
+-------+-----------------------------------------------------------+
| 3 | Name: Serial Number |
| | Identifiers: serialNumber |
| | OID: 2.5.4.5 |
| | DER: 06 03 55 04 05 |
| | Comments: |
+-------+-----------------------------------------------------------+
| 4 | Name: Country |
| | Identifiers: countryName, c |
| | OID: 2.5.4.6 |
| | DER: 06 03 55 04 06 |
| | Comments: |
+-------+-----------------------------------------------------------+
| 5 | Name: Locality |
| | Identifiers: localityName, locality, l |
| | OID: 2.5.4.7 |
| | DER: 06 03 55 04 07 |
| | Comments: |
+-------+-----------------------------------------------------------+
| 6 | Name: State or Province |
| | Identifiers: stateOrProvinceName, st |
| | OID: 2.5.4.8 |
| | DER: 06 03 55 04 08 |
| | Comments: |
+-------+-----------------------------------------------------------+
| 7 | Name: Street Address |
| | Identifiers: streetAddress, street |
| | OID: 2.5.4.9 |
| | DER: 06 03 55 04 09 |
| | Comments: |
+-------+-----------------------------------------------------------+
| 8 | Name: Organization |
| | Identifiers: organizationName, o |
| | OID: 2.5.4.10 |
| | DER: 06 03 55 04 0A |
| | Comments: |
+-------+-----------------------------------------------------------+
| 9 | Name: Organizational Unit |
| | Identifiers: organizationalUnitName, ou |
| | OID: 2.5.4.11 |
| | DER: 06 03 55 04 0B |
| | Comments: |
+-------+-----------------------------------------------------------+
| 10 | Name: Title |
| | Identifiers: title |
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| | OID: 2.5.4.12 |
| | DER: 06 03 55 04 0C |
| | Comments: |
+-------+-----------------------------------------------------------+
| 11 | Name: Business Category |
| | Identifiers: businessCategory |
| | OID: 2.5.4.15 |
| | DER: 06 03 55 04 0F |
| | Comments: |
+-------+-----------------------------------------------------------+
| 12 | Name: Postal Code |
| | Identifiers: postalCode |
| | OID: 2.5.4.17 |
| | DER: 06 03 55 04 11 |
| | Comments: |
+-------+-----------------------------------------------------------+
| 13 | Name: Given Name |
| | Identifiers: givenName |
| | OID: 2.5.4.42 |
| | DER: 06 03 55 04 2A |
| | Comments: |
+-------+-----------------------------------------------------------+
| 14 | Name: Initials |
| | Identifiers: initials |
| | OID: 2.5.4.43 |
| | DER: 06 03 55 04 2B |
| | Comments: |
+-------+-----------------------------------------------------------+
| 15 | Name: Generation Qualifier |
| | Identifiers: generationQualifier |
| | OID: 2.5.4.44 |
| | DER: 06 03 55 04 2C |
| | Comments: |
+-------+-----------------------------------------------------------+
| 16 | Name: DN Qualifier |
| | Identifiers: dnQualifier |
| | OID: 2.5.4.46 |
| | DER: 06 03 55 04 2E |
| | Comments: |
+-------+-----------------------------------------------------------+
| 17 | Name: Pseudonym |
| | Identifiers: pseudonym |
| | OID: 2.5.4.65 |
| | DER: 06 03 55 04 41 |
| | Comments: |
+-------+-----------------------------------------------------------+
| 18 | Name: Organization Identifier |
| | Identifiers: organizationIdentifier |
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| | OID: 2.5.4.97 |
| | DER: 06 03 55 04 61 |
| | Comments: |
+-------+-----------------------------------------------------------+
| 19 | Name: Inc. Locality |
| | Identifiers: jurisdictionOfIncorporationLocalityName |
| | OID: 1.3.6.1.4.1.311.60.2.1.1 |
| | DER: 06 0B 2B 06 01 04 01 82 37 3C 02 01 01 |
| | Comments: |
+-------+-----------------------------------------------------------+
| 20 | Name: Inc. State or Province |
| | Identifiers: jurisdictionOfIncorporation |
| | StateOrProvinceName |
| | OID: 1.3.6.1.4.1.311.60.2.1.2 |
| | DER: 06 0B 2B 06 01 04 01 82 37 3C 02 01 02 |
| | Comments: |
+-------+-----------------------------------------------------------+
| 21 | Name: Inc. Country |
| | Identifiers: jurisdictionOfIncorporationCountryName |
| | OID: 1.3.6.1.4.1.311.60.2.1.3 |
| | DER: 06 0B 2B 06 01 04 01 82 37 3C 02 01 03 |
| | Comments: |
+-------+-----------------------------------------------------------+
| 22 | Name: Domain Component |
| | Identifiers: domainComponent, dc |
| | OID: 0.9.2342.19200300.100.1.25 |
| | DER: 06 0A 09 92 26 89 93 F2 2C 64 01 19 |
| | Comments: |
+-------+-----------------------------------------------------------+
| 24 | Name: Postal Address |
| | Identifiers: postalAddress |
| | OID: 2.5.4.16 |
| | DER: 06 03 55 04 10 |
| | Comments: |
+-------+-----------------------------------------------------------+
| 25 | Name: Name |
| | Identifiers: name |
| | OID: 2.5.4.41 |
| | DER: 06 03 55 04 29 |
| | Comments: |
+-------+-----------------------------------------------------------+
| 26 | Name: Telephone Number |
| | Identifiers: telephoneNumber |
| | OID: 2.5.4.20 |
| | DER: 06 03 55 04 14 |
| | Comments: |
+-------+-----------------------------------------------------------+
| 27 | Name: Directory Management Domain Name |
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| | Identifiers: dmdName |
| | OID: 2.5.4.54 |
| | DER: 06 03 55 04 36 |
| | Comments: |
+-------+-----------------------------------------------------------+
| 28 | Name: userid |
| | Identifiers: uid |
| | OID: 0.9.2342.19200300.100.1.1 |
| | DER: 06 0A 09 92 26 89 93 F2 2C 64 01 01 |
| | Comments: |
+-------+-----------------------------------------------------------+
| 29 | Name: Unstructured Name |
| | Identifiers: unstructuredName |
| | OID: 1.2.840.113549.1.9.2 |
| | DER: 06 09 2A 86 48 86 F7 0D 01 09 02 |
| | Comments: |
+-------+-----------------------------------------------------------+
| 30 | Name: Unstructured Address |
| | Identifiers: unstructuredAddress |
| | OID: 1.2.840.113549.1.9.8 |
| | DER: 06 0A 2A 86 48 86 F7 0D 01 09 08 00 |
| | Comments: |
+-------+-----------------------------------------------------------+
Figure 6: C509 Attributes
9.3. C509 Extensions Registry
IANA has created a new registry titled "C509 Extensions Registry"
under the new heading "CBOR Encoded X509 Certificates (C509
Certificates)". The columns of the registry are Value, Name,
Identifiers, OID, DER, Comments, extensionValue, and Reference, where
Value is an positive integer, and the other columns are text strings.
The registry also contains CSR attributes for use in Certificate
Requests, see Section 4. For values in the interval [1, 23] the
registration procedure is "IETF Review" and "Expert Review". For all
other values the registration procedure is "Expert Review". The
initial contents of the registry are:
+-------+-----------------------------------------------------------+
| Value | Extension |
+=======+===========================================================+
| 1 | Name: Subject Key Identifier |
| | Identifiers: subjectKeyIdentifier |
| | OID: 2.5.29.14 |
| | DER: 06 03 55 1D 0E |
| | Comments: |
| | extensionValue: SubjectKeyIdentifier |
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+-------+-----------------------------------------------------------+
| 2 | Name: Key Usage |
| | Identifiers: keyUsage |
| | OID: 2.5.29.15 |
| | DER: 06 03 55 1D 0F |
| | Comments: |
| | AttributeValue: KeyUsage |
+-------+-----------------------------------------------------------+
| 3 | Name: Subject Alternative Name |
| | Identifiers: subjectAltName |
| | OID: 2.5.29.17 |
| | DER: 06 03 55 1D 11 |
| | Comments: |
| | extensionValue: SubjectAltName |
+-------+-----------------------------------------------------------+
| 4 | Name: Basic Constraints |
| | Identifiers: basicConstraints |
| | OID: 2.5.29.19 |
| | DER: 06 03 55 1D 13 |
| | Comments: |
| | extensionValue: BasicConstraints |
+-------+-----------------------------------------------------------+
| 5 | Name: CRL Distribution Points |
| | Identifiers: cRLDistributionPoints |
| | OID: 2.5.29.31 |
| | DER: 06 03 55 1D 1F |
| | Comments: |
| | extensionValue: CRLDistributionPoints |
+-------+-----------------------------------------------------------+
| 6 | Name: Certificate Policies |
| | Identifiers: certificatePolicies |
| | OID: 2.5.29.32 |
| | DER: 06 03 55 1D 20 |
| | Comments: |
| | extensionValue: CertificatePolicies |
+-------+-----------------------------------------------------------+
| 7 | Name: Authority Key Identifier |
| | Identifiers: authorityKeyIdentifier |
| | OID: 2.5.29.35 |
| | DER: 06 03 55 1D 23 |
| | Comments: |
| | extensionValue: AuthorityKeyIdentifier |
+-------+-----------------------------------------------------------+
| 8 | Name: Extended Key Usage |
| | Identifiers: extKeyUsage |
| | OID: 2.5.29.37 |
| | DER: 06 03 55 1D 25 |
| | Comments: |
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| | extensionValue: ExtKeyUsageSyntax |
+-------+-----------------------------------------------------------+
| 9 | Name: Authority Information Access |
| | Identifiers: authorityInfoAccess |
| | OID: 1.3.6.1.5.5.7.1.1 |
| | DER: 06 08 2B 06 01 05 05 07 01 01 |
| | Comments: |
| | extensionValue: AuthorityInfoAccessSyntax |
+-------+-----------------------------------------------------------+
| 10 | Name: Signed Certificate Timestamp List |
| | Identifiers: |
| | OID: 1.3.6.1.4.1.11129.2.4.2 |
| | DER: 06 0A 2B 06 01 04 01 D6 79 02 04 02 |
| | Comments: |
| | extensionValue: SignedCertificateTimestampList |
+-------+-----------------------------------------------------------+
| 24 | Name: Subject Directory Attributes |
| | Identifiers: subjectDirectoryAttributes |
| | OID: 2.5.29.9 |
| | DER: 06 03 55 1D 09 |
| | Comments: |
| | extensionValue: SubjectDirectoryAttributes |
+-------+-----------------------------------------------------------+
| 25 | Name: Issuer Alternative Name |
| | Identifiers: issuerAltName |
| | OID: 2.5.29.18 |
| | DER: 06 03 55 1D 12 |
| | Comments: |
| | extensionValue: IssuerAltName |
+-------+-----------------------------------------------------------+
| 26 | Name: Name Constraints |
| | Identifiers: nameConstraints |
| | OID: 2.5.29.30 |
| | DER: 06 03 55 1D 1E |
| | Comments: |
| | extensionValue: NameConstraints |
+-------+-----------------------------------------------------------+
| 27 | Name: Policy Mappings |
| | Identifiers: policyMappings |
| | OID: 2.5.29.33 |
| | DER: 06 03 55 1D 21 |
| | Comments: |
| | extensionValue: PolicyMappings |
+-------+-----------------------------------------------------------+
| 28 | Name: Policy Constraints |
| | Identifiers: policyConstraints |
| | OID: 2.5.29.36 |
| | DER: 06 03 55 1D 24 |
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| | Comments: |
| | extensionValue: PolicyConstraints |
+-------+-----------------------------------------------------------+
| 29 | Name: Freshest CRL |
| | Identifiers: freshestCRL |
| | OID: 2.5.29.46 |
| | DER: 06 03 55 1D 2E |
| | Comments: |
| | extensionValue: FreshestCRL |
+-------+-----------------------------------------------------------+
| 30 | Name: Inhibit anyPolicy |
| | Identifiers: inhibitAnyPolicy |
| | OID: 2.5.29.54 |
| | DER: 06 03 55 1D 36 |
| | Comments: |
| | extensionValue: InhibitAnyPolicy |
+-------+-----------------------------------------------------------+
| 31 | Name: Subject Information Access |
| | Identifiers: subjectInfoAccess |
| | OID: 1.3.6.1.5.5.7.1.11 |
| | DER: 06 08 2B 06 01 05 05 07 01 0B |
| | Comments: |
| | extensionValue: SubjectInfoAccessSyntax |
+-------+-----------------------------------------------------------+
| 32 | Name: IP Resources |
| | Identifiers: id-pe-ipAddrBlocks |
| | OID: 1.3.6.1.5.5.7.1.7 |
| | DER: 06 08 2B 06 01 05 05 07 01 07 |
| | Comments: |
| | extensionValue: IPAddrBlocks |
+-------+-----------------------------------------------------------+
| 33 | Name: AS Resources |
| | Identifiers: autonomousSysIds |
| | OID: 1.3.6.1.5.5.7.1.8 |
| | DER: 06 08 2B 06 01 05 05 07 01 08 |
| | Comments: |
| | extensionValue: ASIdentifiers |
+-------+-----------------------------------------------------------+
| 34 | Name: IP Resources v2 |
| | Identifiers: id-pe-ipAddrBlocks-v2 |
| | OID: 1.3.6.1.5.5.7.1.28 |
| | DER: 06 08 2B 06 01 05 05 07 01 1C |
| | Comments: |
| | extensionValue: IPAddrBlocks |
+-------+-----------------------------------------------------------+
| 35 | Name: AS Resources v2 |
| | Identifiers: autonomousSysIds-v2 |
| | OID: 1.3.6.1.5.5.7.1.29 |
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| | DER: 06 08 2B 06 01 05 05 07 01 1D |
| | Comments: |
| | extensionValue: ASIdentifiers |
+-------+-----------------------------------------------------------+
| 36 | Name: Biometric Information |
| | Identifiers: biometricInfo |
| | OID: 1.3.6.1.5.5.7.1.2 |
| | DER: 06 08 2B 06 01 05 05 07 01 02 |
| | Comments: |
| | extensionValue: |
+-------+-----------------------------------------------------------+
| 37 | Name: Precertificate Signing Certificate |
| | Identifiers: |
| | OID: 1.3.6.1.4.1.11129.2.4.4 |
| | DER: 06 0A 2B 06 01 04 01 D6 79 02 04 04 |
| | Comments: |
| | extensionValue: |
+-------+-----------------------------------------------------------+
| 38 | Name: OCSP No Check |
| | Identifiers: id-pkix-ocsp-nocheck |
| | OID: 1.3.6.1.5.5.7.48.1.5 |
| | DER: 06 09 2B 06 01 05 05 07 30 01 05 |
| | Comments: |
| | extensionValue: |
+-------+-----------------------------------------------------------+
| 39 | Name: Qualified Certificate Statements |
| | Identifiers: id-pe-qcStatements |
| | OID: 1.3.6.1.5.5.7.1.3 |
| | DER: 06 08 2B 06 01 05 05 07 01 03 |
| | Comments: |
| | extensionValue: |
+-------+-----------------------------------------------------------+
| 40 | Name: S/MIME Capabilities |
| | Identifiers: smimeCapabilities |
| | OID: 1.2.840.113549.1.9.15 |
| | DER: 06 09 2A 86 48 86 F7 0D 01 09 0F |
| | Comments: |
| | extensionValue: |
+-------+-----------------------------------------------------------+
| 41 | Name: TLS Features |
| | Identifiers: id-pe-tlsfeature |
| | OID: 1.3.6.1.5.5.7.1.24 |
| | DER: 06 08 2B 06 01 05 05 07 01 18 |
| | Comments: |
| | extensionValue: |
+-------+-----------------------------------------------------------+
| 42 | Name: Subject Information Access |
| | Identifiers: id-pe-subjectInfoAccess |
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| | OID: 1.3.6.1.5.5.7.1.11 |
| | DER: 06 08 2B 06 01 05 05 07 01 0B |
| | Comments: |
| | extensionValue: |
+-------+-----------------------------------------------------------+
| 255 | Name: Challenge Password |
| | Identifiers: challengePassword |
| | OID: 1.2.840.113549.1.9.7 |
| | DER: 06 09 2A 86 48 86 F7 0D 01 09 07 |
| | Comments: CSR Attribute |
| | extensionValue: ChallengePassword |
+-------+-----------------------------------------------------------+
Figure 7: C509 Extensions and CSR Attributes
9.4. C509 Certificate Policies Registry
IANA has created a new registry titled "C509 Certificate Policies
Registry" under the new heading "CBOR Encoded X509 Certificates (C509
Certificates)". The columns of the registry are Value, Name,
Identifiers, OID, DER, Comments, and Reference, where Value is an
integer, and the other columns are text strings. For values in the
interval [-24, 23] the registration procedure is "IETF Review" and
"Expert Review". For all other values the registration procedure is
"Expert Review". The initial contents of the registry are:
+-------+-----------------------------------------------------------+
| Value | Certificate Policy |
+=======+===========================================================+
| 0 | Name: Any Policy |
| | Identifiers: anyPolicy |
| | OID: 2.5.29.32.0 |
| | DER: 06 04 55 1D 20 00 |
| | Comments: |
+-------+-----------------------------------------------------------+
| 1 | Name: Domain Validation (DV) |
| | Identifiers: domain-validated |
| | OID: 2.23.140.1.2.1 |
| | DER: 06 06 67 81 0C 01 02 01 |
| | Comments: |
+-------+-----------------------------------------------------------+
| 2 | Name: Organization Validation (OV) |
| | Identifiers: organization-validated |
| | OID: 2.23.140.1.2.2 |
| | DER: 06 06 67 81 0C 01 02 02 |
| | Comments: |
+-------+-----------------------------------------------------------+
| 3 | Name: Individual Validation (IV) |
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| | Identifiers: individual-validated |
| | OID: 2.23.140.1.2.3 |
| | DER: 06 06 67 81 0C 01 02 03 |
| | Comments: |
+-------+-----------------------------------------------------------+
| 4 | Name: Extended Validation (EV) |
| | Identifiers: ev-guidelines |
| | OID: 2.23.140.1.1 |
| | DER: 06 05 67 81 0C 01 01 |
| | Comments: |
+-------+-----------------------------------------------------------+
| 7 | Name: Resource PKI (RPKI) |
| | Identifiers: id-cp-ipAddr-asNumber |
| | OID: 1.3.6.1.5.5.7.14.2 |
| | DER: 06 08 2B 06 01 05 05 07 0E 02 |
| | Comments: |
+-------+-----------------------------------------------------------+
| 8 | Name: Resource PKI (RPKI) (Alternative) |
| | Identifiers: id-cp-ipAddr-asNumber-v2 |
| | OID: 1.3.6.1.5.5.7.14.3 |
| | DER: 06 08 2B 06 01 05 05 07 0E 03 |
| | Comments: |
+-------+-----------------------------------------------------------+
| 10 | Name: Remote SIM Provisioning Role |
| | Certificate Issuer |
| | Identifiers: id-rspRole-ci |
| | OID: 2.23.146.1.2.1.0 |
| | DER: 06 07 67 81 12 01 02 01 00 |
| | Comments: |
+-------+-----------------------------------------------------------+
| 11 | Name: Remote SIM Provisioning Role |
| | eUICC |
| | Identifiers: id-rspRole-euicc |
| | OID: 2.23.146.1.2.1.1 |
| | DER: 06 07 67 81 12 01 02 01 01 |
| | Comments: |
+-------+-----------------------------------------------------------+
| 12 | Name: Remote SIM Provisioning Role |
| | eUICC Manufacturer |
| | Identifiers: id-rspRole-eum |
| | OID: 2.23.146.1.2.1.2 |
| | DER: 06 07 67 81 12 01 02 01 02 |
| | Comments: |
+-------+-----------------------------------------------------------+
| 13 | Name: Remote SIM Provisioning Role |
| | SM-DP+ TLS |
| | Identifiers: id-rspRole-dp-tls |
| | OID: 2.23.146.1.2.1.3 |
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| | DER: 06 07 67 81 12 01 02 01 03 |
| | Comments: |
+-------+-----------------------------------------------------------+
| 14 | Name: Remote SIM Provisioning Role |
| | SM-DP+ Authentication |
| | Identifiers: id-rspRole-dp-auth |
| | OID: 2.23.146.1.2.1.4 |
| | DER: 06 07 67 81 12 01 02 01 04 |
| | Comments: |
+-------+-----------------------------------------------------------+
| 15 | Name: Remote SIM Provisioning Role |
| | SM-DP+ Profile Binding |
| | Identifiers: id-rspRole-dp-pb |
| | OID: 2.23.146.1.2.1.5 |
| | DER: 06 07 67 81 12 01 02 01 05 |
| | Comments: |
+-------+-----------------------------------------------------------+
| 16 | Name: Remote SIM Provisioning Role |
| | SM-DS TLS |
| | Identifiers: id-rspRole-ds-tls |
| | OID: 2.23.146.1.2.1.6 |
| | DER: 06 07 67 81 12 01 02 01 06 |
| | Comments: |
+-------+-----------------------------------------------------------+
| 17 | Name: Remote SIM Provisioning Role |
| | SM-DS Authentication |
| | Identifiers: id-rspRole-ds-auth |
| | OID: 2.23.146.1.2.1.7 |
| | DER: 06 07 67 81 12 01 02 01 07 |
| | Comments: |
+-------+-----------------------------------------------------------+
Figure 8: C509 Certificate Policies
9.5. C509 Policies Qualifiers Registry
IANA has created a new registry titled "C509 Policies Qualifiers
Registry" under the new heading "CBOR Encoded X509 Certificates (C509
Certificates)". The columns of the registry are Value, Name,
Identifiers, OID, DER, Comments, and Reference, where Value is an
integer, and the other columns are text strings. For values in the
interval [-24, 23] the registration procedure is "IETF Review" and
"Expert Review". For all other values the registration procedure is
"Expert Review". The initial contents of the registry are:
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+-------+-----------------------------------------------------------+
| Value | Certificate Policy |
+=======+===========================================================+
| 1 | Name: Certification Practice Statement |
| | Identifiers: id-qt-cps, cps |
| | OID: 1.3.6.1.5.5.7.2.1 |
| | DER: 06 08 2B 06 01 05 05 07 02 01 |
| | Comments: |
+-------+-----------------------------------------------------------+
| 2 | Name: User Notice |
| | Identifiers: id-qt-unotice, unotice |
| | OID: 1.3.6.1.5.5.7.2.2 |
| | DER: 06 08 2B 06 01 05 05 07 02 02 |
| | Comments: |
+-------+-----------------------------------------------------------+
Figure 9: C509 Policies Qualifiers
9.6. C509 Information Access Registry
IANA has created a new registry titled "C509 Information Access
Registry" under the new heading "CBOR Encoded X509 Certificates (C509
Certificates)". The columns of the registry are Value, Name,
Identifiers, OID, DER, Comments, and Reference, where Value is an
integer, and the other columns are text strings. For values in the
interval [-24, 23] the registration procedure is "IETF Review" and
"Expert Review". For all other values the registration procedure is
"Expert Review". The initial contents of the registry are:
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+-------+-----------------------------------------------------------+
| Value | Information Access |
+=======+===========================================================+
| 1 | Name: OCSP |
| | Identifiers: id-ad-ocsp, id-pkix-ocsp |
| | OID: 1.3.6.1.5.5.7.48.1 |
| | DER: 06 08 2B 06 01 05 05 07 30 01 |
| | Comments: |
+-------+-----------------------------------------------------------+
| 2 | Name: CA Issuers |
| | Identifiers: id-ad-caIssuers, caIssuers |
| | OID: 1.3.6.1.5.5.7.48.2 |
| | DER: 06 08 2B 06 01 05 05 07 30 02 |
| | Comments: |
+-------+-----------------------------------------------------------+
| 3 | Name: Time Stamping |
| | Identifiers: id-ad-timeStamping, timeStamping |
| | OID: 1.3.6.1.5.5.7.48.3 |
| | DER: 06 08 2B 06 01 05 05 07 30 03 |
| | Comments: |
+-------+-----------------------------------------------------------+
| 5 | Name: CA Repository |
| | Identifiers: id-ad-caRepository |
| | OID: 1.3.6.1.5.5.7.48.5 |
| | DER: 06 08 2B 06 01 05 05 07 30 05 |
| | Comments: |
+-------+-----------------------------------------------------------+
| 10 | Name: RPKI Manifest |
| | Identifiers: id-ad-rpkiManifest |
| | OID: 1.3.6.1.5.5.7.48.10 |
| | DER: 06 08 2B 06 01 05 05 07 30 0A |
| | Comments: RFC 6487 |
+-------+-----------------------------------------------------------+
| 11 | Name: Signed Object |
| | Identifiers: id-ad-signedObject |
| | OID: 1.3.6.1.5.5.7.48.11 |
| | DER: 06 08 2B 06 01 05 05 07 30 0B |
| | Comments: RFC 6487 |
+-------+-----------------------------------------------------------+
| 13 | Name: RPKI Notify |
| | Identifiers: id-ad-rpkiNotify |
| | OID: 1.3.6.1.5.5.7.48.13 |
| | DER: 06 08 2B 06 01 05 05 07 30 0D |
| | Comments: RFC 8182 |
+-------+-----------------------------------------------------------+
Figure 10: C509 Information Accesses
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9.7. C509 Extended Key Usages Registry
IANA has created a new registry titled "C509 Extended Key Usages
Registry" under the new heading "CBOR Encoded X509 Certificates (C509
Certificates)". The columns of the registry are Value, Name,
Identifiers, OID, DER, Comments, and Reference, where Value is an
integer, and the other columns are text strings. For values in the
interval [-24, 23] the registration procedure is "IETF Review" and
"Expert Review". For all other values the registration procedure is
"Expert Review". The initial contents of the registry are:
+-------+---------------------------------------------------------+
| Value | Extended Key Usage |
+=======+=========================================================+
| 0 | Name: Any Extended Key Usage |
| | Identifiers: anyExtendedKeyUsage |
| | OID: 2.5.29.37.0 |
| | DER: 06 04 55 1D 25 00 |
| | Comments: RFC 5280 |
+-------+---------------------------------------------------------+
| 1 | Name: TLS Server authentication |
| | Identifiers: id-kp-serverAuth |
| | OID: 1.3.6.1.5.5.7.3.1 |
| | DER: 06 08 2B 06 01 05 05 07 03 01 |
| | Comments: RFC 5280 |
+-------+---------------------------------------------------------+
| 2 | Name: TLS Client Authentication |
| | Identifiers: id-kp-clientAuth |
| | OID: 1.3.6.1.5.5.7.3.2 |
| | DER: 06 08 2B 06 01 05 05 07 03 02 |
| | Comments: RFC 5280 |
+-------+---------------------------------------------------------+
| 3 | Name: Code Signing |
| | Identifiers: id-kp-codeSigning |
| | OID: 1.3.6.1.5.5.7.3.3 |
| | DER: 06 08 2B 06 01 05 05 07 03 03 |
| | Comments: RFC 5280 |
+-------+---------------------------------------------------------+
| 4 | Name: Email protection (S/MIME) |
| | Identifiers: id-kp-emailProtection |
| | OID: 1.3.6.1.5.5.7.3.4 |
| | DER: 06 08 2B 06 01 05 05 07 03 04 |
| | Comments: RFC 5280 |
+-------+---------------------------------------------------------+
| 8 | Name: Time Stamping |
| | Identifiers: id-kp-timeStamping, timestamping |
| | OID: 1.3.6.1.5.5.7.3.8 |
| | DER: 06 08 2B 06 01 05 05 07 03 08 |
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| | Comments: |
+-------+---------------------------------------------------------+
| 9 | Name: OCSP Signing |
| | Identifiers: id-kp-OCSPSigning |
| | OID: 1.3.6.1.5.5.7.3.9 |
| | DER: 06 08 2B 06 01 05 05 07 03 09 |
| | Comments: RFC 5280 |
+-------+---------------------------------------------------------+
| 10 | Name: Kerberos PKINIT Client Auth |
| | Identifiers: id-pkinit-KPClientAuth |
| | OID: 1.3.6.1.5.2.3.4 |
| | DER: 06 07 2B 06 01 05 02 03 04 |
| | Comments: RFC 4556 |
+-------+---------------------------------------------------------+
| 11 | Name: Kerberos PKINIT KDC |
| | Identifiers: id-pkinit-KPKdc |
| | OID: 1.3.6.1.5.2.3.5 |
| | DER: 06 07 2B 06 01 05 02 03 05 |
| | Comments: RFC 4556 |
+-------+---------------------------------------------------------+
| 12 | Name: SSH Client |
| | Identifiers: id-kp-secureShellClient |
| | OID: 1.3.6.1.5.5.7.3.21 |
| | DER: 06 08 2B 06 01 05 05 07 03 15 |
| | Comments: RFC 6187 |
+-------+---------------------------------------------------------+
| 13 | Name: SSH Server |
| | Identifiers: id-kp-secureShellServer |
| | OID: 1.3.6.1.5.5.7.3.22 |
| | DER: 06 08 2B 06 01 05 05 07 03 16 |
| | Comments: RFC 6187 |
+-------+---------------------------------------------------------+
| 14 | Name: Bundle Security |
| | Identifiers: id-kp-bundleSecurity |
| | OID: 1.3.6.1.5.5.7.3.35 |
| | DER: 06 08 2B 06 01 05 05 07 03 23 |
| | Comments: RFC 9174 |
+-------+---------------------------------------------------------+
Figure 11: C509 Extended Key Usages
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9.8. C509 General Names Registry
IANA has created a new registry titled "C509 General Names Registry"
under the new heading "CBOR Encoded X509 Certificates (C509
Certificates)". The columns of the registry are Value, General Name,
and Reference, where Value is an integer, and the other columns are
text strings. For values in the interval [-24, 23] the registration
procedure is "IETF Review" and "Expert Review". For all other values
the registration procedure is "Expert Review". The initial contents
of the registry are:
+-------+-----------------------------------------------------------+
| Value | General Names |
+=======+===========================================================+
| -3 | Name: otherName with BundleEID |
| | Comments: id-on-bundleEID |
| | (1.3.6.1.5.5.7.8.11) |
| | 06 08 2B 06 01 05 05 07 08 0B |
| | Value: eid-structure from RFC 9171 |
+-------+-----------------------------------------------------------+
| -2 | Name: otherName with SmtpUTF8Mailbox |
| | Comments: id-on-SmtpUTF8Mailbox |
| | (1.3.6.1.5.5.7.8.9) |
| | 06 08 2B 06 01 05 05 07 08 09 |
| | Value: text |
+-------+-----------------------------------------------------------+
| -1 | Name: otherName with hardwareModuleName |
| | Comments: id-on-hardwareModuleNamee |
| | (1.3.6.1.5.5.7.8.4) |
| | 06 08 2B 06 01 05 05 07 08 04 |
| | Value: [ ~oid, bytes ] |
+-------+-----------------------------------------------------------+
| 0 | Name: otherName |
| | Comments: |
| | Value: [ ~oid, bytes ] |
+-------+-----------------------------------------------------------+
| 1 | Name: rfc822Name |
| | Comments: |
| | Value: text |
+-------+-----------------------------------------------------------+
| 2 | Name: dNSName |
| | Comments: |
| | Value: text |
+-------+-----------------------------------------------------------+
| 4 | Name: directoryName |
| | Comments: |
| | Value: Name |
+-------+-----------------------------------------------------------+
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| 6 | Name: uniformResourceIdentifier |
| | Comments: |
| | Value: text |
+-------+-----------------------------------------------------------+
| 7 | Name: iPAddress |
| | Comments: |
| | Value: bytes |
+-------+-----------------------------------------------------------+
| 8 | Name: registeredID |
| | Comments: |
| | Value: ~oid |
+-------+-----------------------------------------------------------+
Figure 12: C509 General Names
9.9. C509 Signature Algorithms Registry
IANA has created a new registry titled "C509 Signature Algorithms"
under the new heading "CBOR Encoded X509 Certificates (C509
Certificates)". The registry includes both signature algorithms and
non-signature proof-of-possession algorithms. The columns of the
registry are Value, Name, Identifiers, OID, Parameters, DER,
Comments, and Reference, where Value is an integer, and the other
columns are text strings. For values in the interval [-24, 23] the
registration procedure is "IETF Review" and "Expert Review". For all
other values the registration procedure is "Expert Review". The
initial contents of the registry are:
+-------+-----------------------------------------------------------+
| Value | X.509 Signature Algorithms |
+=======+===========================================================+
| -256 | Name: RSASSA-PKCS1-v1_5 with SHA-1 |
| | Identifiers: sha1-with-rsa-signature, |
| | sha1WithRSAEncryption, |
| | sha-1WithRSAEncryption |
| | OID: 1.2.840.113549.1.1.5 |
| | Parameters: NULL |
| | DER: 30 0D 06 09 2A 86 48 86 F7 0D 01 01 05 05 00 |
| | Comments: Don't use |
+-------+-----------------------------------------------------------+
| -255 | Name: ECDSA with SHA-1 |
| | Identifiers: ecdsa-with-SHA1 |
| | OID: 1.2.840.10045.4.1 |
| | Parameters: Absent |
| | DER: 30 09 06 07 2A 86 48 CE 3D 04 01 |
| | Comments: Don't use. Compressed signature value |
+-------+-----------------------------------------------------------+
| 0 | Name: ECDSA with SHA-256 |
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| | Identifiers: ecdsa-with-SHA256 |
| | OID: 1.2.840.10045.4.3.2 |
| | Parameters: Absent |
| | DER: 30 0A 06 08 2A 86 48 CE 3D 04 03 02 |
| | Comments: Compressed signature value |
+-------+-----------------------------------------------------------+
| 1 | Name: ECDSA with SHA-384 |
| | Identifiers: ecdsa-with-SHA384 |
| | OID: 1.2.840.10045.4.3.3 |
| | Parameters: Absent |
| | DER: 30 0A 06 08 2A 86 48 CE 3D 04 03 03 |
| | Comments: Compressed signature value |
+-------+-----------------------------------------------------------+
| 2 | Name: ECDSA with SHA-512 |
| | Identifiers: ecdsa-with-SHA512 |
| | OID: 1.2.840.10045.4.3.4 |
| | Parameters: Absent |
| | DER: 30 0A 06 08 2A 86 48 CE 3D 04 03 04 |
| | Comments: Compressed signature value |
+-------+-----------------------------------------------------------+
| 3 | Name: ECDSA with SHAKE128 |
| | Identifiers: id-ecdsa-with-shake128 |
| | OID: 1.3.6.1.5.5.7.6.32 |
| | Parameters: Absent |
| | DER: 30 0A 06 08 2B 06 01 05 05 07 06 20 |
| | Comments: Compressed signature value |
+-------+-----------------------------------------------------------+
| 4 | Name: ECDSA with SHAKE256 |
| | Identifiers: id-ecdsa-with-shake256 |
| | OID: 1.3.6.1.5.5.7.6.33 |
| | Parameters: Absent |
| | DER: 30 0A 06 08 2B 06 01 05 05 07 06 21 |
| | Comments: Compressed signature value |
+-------+-----------------------------------------------------------+
| 12 | Name: Ed25519 |
| | Identifiers: id-Ed25519, id-EdDSA25519 |
| | OID: 1.3.101.112 |
| | Parameters: Absent |
| | DER: 30 05 06 03 2B 65 70 |
| | Comments: |
+-------+-----------------------------------------------------------+
| 13 | Name: Ed448 |
| | Identifiers: id-Ed448, id-EdDSA448 |
| | OID: 1.3.101.113 |
| | Parameters: Absent |
| | DER: 30 05 06 03 2B 65 71 |
| | Comments: |
+-------+-----------------------------------------------------------+
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| 14 | Name: SHA-256 with HMAC-SHA256 |
| | Identifiers: sa-ecdhPop-sha256-hmac-sha256 |
| | OID: 1.3.6.1.5.5.7.6.26 |
| | Parameters: Absent |
| | DER: 30 0A 06 08 2B 06 01 05 05 07 06 1A |
| | Comments: Proof-of-possession algorithm, indexed with |
| | KDF and MAC, see RFC 6955. Requires |
| | recipient public static Diffie-Hellman key. |
+-------+-----------------------------------------------------------+
| 15 | Name: SHA-384 with HMAC-SHA384 |
| | Identifiers: sa-ecdhPop-sha384-hmac-sha384 |
| | OID: 1.3.6.1.5.5.7.6.27 |
| | Parameters: Absent |
| | DER: 30 0A 06 08 2B 06 01 05 05 07 06 1B |
| | Comments: Proof-of-possession algorithm, indexed with |
| | KDF and MAC, see RFC 6955. Requires |
| | recipient public static Diffie-Hellman key. |
+-------+-----------------------------------------------------------+
| 16 | Name: SHA-512 with HMAC-SHA512 |
| | Identifiers: sa-ecdhPop-sha512-hmac-sha512 |
| | OID: 1.3.6.1.5.5.7.6.28 |
| | Parameters: Absent |
| | DER: 30 0A 06 08 2B 06 01 05 05 07 06 1C |
| | Comments: Proof-of-possession algorithm, indexed with |
| | KDF and MAC, see RFC 6955. Requires |
| | recipient public static Diffie-Hellman key. |
+-------+-----------------------------------------------------------+
| 23 | Name: RSASSA-PKCS1-v1_5 with SHA-256 |
| | Identifiers: sha256WithRSAEncryption |
| | OID: 1.2.840.113549.1.1.11 |
| | Parameters: NULL |
| | DER: 30 0B 06 09 2A 86 48 86 F7 0D 01 01 0B 05 00 |
| | Comments: |
+-------+-----------------------------------------------------------+
| 24 | Name: RSASSA-PKCS1-v1_5 with SHA-384 |
| | Identifiers: sha384WithRSAEncryption |
| | OID: 1.2.840.113549.1.1.12 |
| | Parameters: NULL |
| | DER: 30 0B 06 09 2A 86 48 86 F7 0D 01 01 0C 05 00 |
| | Comments: |
+-------+-----------------------------------------------------------+
| 25 | Name: RSASSA-PKCS1-v1_5 with SHA-512 |
| | Identifiers: sha512WithRSAEncryption |
| | OID: 1.2.840.113549.1.1.13 |
| | Parameters: NULL |
| | DER: 30 0B 06 09 2A 86 48 86 F7 0D 01 01 0D 05 00 |
| | Comments: |
+-------+-----------------------------------------------------------+
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| 26 | Name: RSASSA-PSS with SHA-256 |
| | Identifiers: rsassa-pss, id-RSASSA-PSS |
| | OID: 1.2.840.113549.1.1.10 |
| | Parameters: SHA-256, MGF-1 with SHA-256, saltLength = 32 |
| | DER: 30 41 06 09 2A 86 48 86 F7 0D 01 01 0A 30 34 |
| | A0 0F 30 0D 06 09 60 86 48 01 65 03 04 02 01 |
| | 05 00 A1 1C 30 1A 06 09 2A 86 48 86 F7 0D 01 |
| | 01 08 30 0D 06 09 60 86 48 01 65 03 04 02 01 |
| | 05 00 a2 03 02 01 20 |
| | Comments: |
+-------+-----------------------------------------------------------+
| 27 | Name: RSASSA-PSS with SHA-384 |
| | Identifiers: rsassa-pss, id-RSASSA-PSS |
| | OID: 1.2.840.113549.1.1.10 |
| | Parameters: SHA-384, MGF-1 with SHA-384, saltLength = 48 |
| | DER: 30 41 06 09 2A 86 48 86 F7 0D 01 01 0A 30 34 |
| | A0 0F 30 0D 06 09 60 86 48 01 65 03 04 02 02 |
| | 05 00 A1 1C 30 1A 06 09 2A 86 48 86 F7 0D 01 |
| | 01 08 30 0D 06 09 60 86 48 01 65 03 04 02 02 |
| | 05 00 A2 03 02 01 30 |
| | Comments: |
+-------+-----------------------------------------------------------+
| 28 | Name: RSASSA-PSS with SHA-512 |
| | Identifiers: rsassa-pss, id-RSASSA-PSS |
| | OID: 1.2.840.113549.1.1.10 |
| | Parameters: SHA-512, MGF-1 with SHA-512, saltLength = 64 |
| | DER: 30 41 06 09 2A 86 48 86 F7 0D 01 01 0A 30 34 |
| | A0 0F 30 0D 06 09 60 86 48 01 65 03 04 02 03 |
| | 05 00 A1 1C 30 1A 06 09 2A 86 48 86 F7 0D 01 |
| | 01 08 30 0D 06 09 60 86 48 01 65 03 04 02 03 |
| | 05 00 A2 03 02 01 40 |
| | Comments: |
+-------+-----------------------------------------------------------+
| 29 | Name: RSASSA-PSS with SHAKE128 |
| | Identifiers: id-RSASSA-PSS-SHAKE128 |
| | OID: 1.3.6.1.5.5.7.6.30 |
| | Parameters: Absent |
| | DER: 30 0A 06 08 2B 06 01 05 05 07 06 1E |
| | Comments: |
+-------+-----------------------------------------------------------+
| 30 | Name: RSASSA-PSS with SHAKE256 |
| | Identifiers: id-RSASSA-PSS-SHAKE256 |
| | OID: 1.3.6.1.5.5.7.6.31 |
| | Parameters: Absent |
| | DER: 30 0A 06 08 2B 06 01 05 05 07 06 1F |
| | Comments: |
+-------+-----------------------------------------------------------+
| 42 | Name: HSS / LMS |
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| | Identifiers: id-alg-hss-lms-hashsig, id-alg-mts-hashsig |
| | OID: 1.2.840.113549.1.9.16.3.17 |
| | Parameters: Absent |
| | DER: 30 0D 06 0B 2A 86 48 86 F7 0D 01 09 10 03 11 |
| | Comments: |
+-------+-----------------------------------------------------------+
| 43 | Name: XMSS |
| | Identifiers: id_alg_xmss |
| | OID: 0.4.0.127.0.15.1.1.13.0 |
| | Parameters: Absent |
| | DER: 30 0B 06 09 04 00 7F 00 0F 01 01 0D 00 |
| | Comments: |
+-------+-----------------------------------------------------------+
| 44 | Name: XMSS^MT |
| | Identifiers: id_alg_xmssmt |
| | OID: 0.4.0.127.0.15.1.1.14.0 |
| | Parameters: Absent |
| | DER: 30 0B 06 09 04 00 7F 00 0F 01 01 0E 00 |
| | Comments: |
+-------+-----------------------------------------------------------+
| 45 | Name: SM2 with SM3 |
| | Identifiers: sm2-with-sm3 |
| | OID: 1.2.156.10197.1.501 |
| | Parameters: Absent |
| | DER: 30 0A 06 08 2A 81 1C CF 55 01 83 75 |
| | Comments: Compressed signature value |
+-------+-----------------------------------------------------------+
Figure 13: C509 Signature Algorithms
9.10. C509 Public Key Algorithms Registry
IANA has created a new registry titled "C509 Public Key Algorithms"
under the new heading "CBOR Encoded X509 Certificates (C509
Certificates)". The columns of the registry are Value, Name,
Identifiers, OID, Parameters, DER, Comments, and Reference, where
Value is an integer, and the other columns are text strings. For
values in the interval [-24, 23] the registration procedure is "IETF
Review" and "Expert Review". For all other values the registration
procedure is "Expert Review". T The initial contents of the registry
are:
+-------+-----------------------------------------------------------+
| Value | X.509 Public Key Algorithms |
+=======+===========================================================+
| 0 | Name: RSA |
| | Identifiers: rsaEncryption |
| | OID: 1.2.840.113549.1.1.1 |
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| | Parameters: NULL |
| | DER: 30 0d 06 09 2a 86 48 86 f7 0d 01 01 01 05 00 |
| | Comments: Compressed subjectPublicKey |
+-------+-----------------------------------------------------------+
| 1 | Name: EC Public Key (Weierstraß) with secp256r1 |
| | Identifiers: ecPublicKey, id-ecPublicKey |
| | OID: 1.2.840.10045.2.1 |
| | Parameters: namedCurve = secp256r1 (1.2.840.10045.3.1.7) |
| | DER: 30 13 06 07 2A 86 48 CE 3D 02 01 06 08 2A 86 |
| | 48 CE 3D 03 01 07 |
| | Comments: Point compressed subjectPublicKey |
| | Also known as P-256, ansip256r1, prime256v1 |
+-------+-----------------------------------------------------------+
| 2 | Name: EC Public Key (Weierstraß) with secp384r1 |
| | Identifiers: ecPublicKey, id-ecPublicKey |
| | OID: 1.2.840.10045.2.1 |
| | Parameters: namedCurve = secp384r1 (1.3.132.0.34) |
| | DER: 30 10 06 07 2A 86 48 CE 3D 02 01 06 05 2B 81 |
| | 04 00 22 |
| | Comments: Point compressed subjectPublicKey |
| | Also known as P-384, ansip384r1 |
+-------+-----------------------------------------------------------+
| 3 | Name: EC Public Key (Weierstraß) with secp521r1 |
| | Identifiers: ecPublicKey, id-ecPublicKey |
| | OID: 1.2.840.10045.2.1 |
| | Parameters: namedCurve = secp521r1 (1.3.132.0.35) |
| | DER: 30 10 06 07 2A 86 48 CE 3D 02 01 06 05 2B 81 |
| | 04 00 23 |
| | Comments: Point compressed subjectPublicKey |
| | Also known as P-521, ansip521r1 |
+-------+-----------------------------------------------------------+
| 8 | Name: X25519 (Montgomery) |
| | Identifiers: id-X25519 |
| | OID: 1.3.101.110 |
| | Parameters: Absent |
| | DER: 30 05 06 03 2B 65 6E |
| | Comments: |
+-------+-----------------------------------------------------------+
| 9 | Name: X448 (Montgomery) |
| | Identifiers: id-X448 |
| | OID: 1.3.101.111 |
| | Parameters: Absent |
| | DER: 30 05 06 03 2B 65 6F |
| | Comments: |
+-------+-----------------------------------------------------------+
| 10 | Name: Ed25519 (Twisted Edwards) |
| | Identifiers: id-Ed25519, id-EdDSA25519 |
| | OID: 1.3.101.112 |
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| | Parameters: Absent |
| | DER: 30 05 06 03 2B 65 70 |
| | Comments: |
+-------+-----------------------------------------------------------+
| 11 | Name: Ed448 (Edwards) |
| | Identifiers: id-Ed448, id-EdDSA448 |
| | OID: 1.3.101.113 |
| | Parameters: Absent |
| | DER: 30 05 06 03 2B 65 71 |
| | Comments: |
+-------+-----------------------------------------------------------+
| 16 | Name: HSS / LMS |
| | Identifiers: id-alg-hss-lms-hashsig, id-alg-mts-hashsig |
| | OID: 1.2.840.113549.1.9.16.3.17 |
| | Parameters: Absent |
| | DER: 30 0D 06 0B 2A 86 48 86 F7 0D 01 09 10 03 11 |
| | Comments: |
+-------+-----------------------------------------------------------+
| 17 | Name: XMSS |
| | Identifiers: id_alg_xmss |
| | OID: 0.4.0.127.0.15.1.1.13.0 |
| | Parameters: Absent |
| | DER: 30 0B 06 09 04 00 7F 00 0F 01 01 0D 00 |
| | Comments: |
+-------+-----------------------------------------------------------+
| 18 | Name: XMSS^MT |
| | Identifiers: id_alg_xmssmt |
| | OID: 0.4.0.127.0.15.1.1.14.0 |
| | Parameters: Absent |
| | DER: 30 0B 06 09 04 00 7F 00 0F 01 01 0E 00 |
| | Comments: |
+-------+-----------------------------------------------------------+
| 24 | Name: EC Public Key (Weierstraß) with |
| | brainpoolP256r1 |
| | Identifiers: ecPublicKey, id-ecPublicKey |
| | OID: 1.2.840.10045.2.1 |
| | Parameters: namedCurve = brainpoolP256r1 |
| | (1.3.36.3.3.2.8.1.1.7) |
| | DER: 30 14 06 07 2A 86 48 CE 3D 02 01 06 09 2B 24 |
| | 03 03 02 08 01 01 07 |
| | Comments: Point compressed subjectPublicKey |
+-------+-----------------------------------------------------------+
| 25 | Name: EC Public Key (Weierstraß) with |
| | brainpoolP384r1 |
| | Identifiers: ecPublicKey, id-ecPublicKey |
| | OID: 1.2.840.10045.2.1 |
| | Parameters: namedCurve = brainpoolP384r1 |
| | (1.3.36.3.3.2.8.1.1.11) |
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| | DER: 30 14 06 07 2A 86 48 CE 3D 02 01 06 09 2B 24 |
| | 03 03 02 08 01 01 0B |
| | Comments: Point compressed subjectPublicKey |
+-------+-----------------------------------------------------------+
| 26 | Name: EC Public Key (Weierstraß) with |
| | brainpoolP512r1 |
| | Identifiers: ecPublicKey, id-ecPublicKey |
| | OID: 1.2.840.10045.2.1 |
| | Parameters: namedCurve = brainpoolP512r1 |
| | (1.3.36.3.3.2.8.1.1.13) |
| | DER: 30 14 06 07 2A 86 48 CE 3D 02 01 06 09 2B 24 |
| | 03 03 02 08 01 01 0D |
| | Comments: Point compressed subjectPublicKey |
+-------+-----------------------------------------------------------+
| 27 | Name: EC Public Key (Weierstraß) with |
| | FRP256v1 |
| | Identifiers: ecPublicKey, id-ecPublicKey |
| | OID: 1.2.840.10045.2.1 |
| | Parameters: namedCurve = FRP256v1 |
| | (1.2.250.1.223.101.256.1) |
| | DER: 30 15 06 07 2A 86 48 CE 3D 02 01 06 0A 2A 81 |
| | 7A 01 81 5F 65 82 00 01 |
| | Comments: Point compressed subjectPublicKey |
+-------+-----------------------------------------------------------+
| 28 | Name: EC Public Key (Weierstraß) with |
| | sm2p256v1 |
| | Identifiers: ecPublicKey, id-ecPublicKey |
| | OID: 1.2.840.10045.2.1 |
| | Parameters: namedCurve = sm2p256v1 |
| | (1.2.156.10197.1.301) |
| | DER: 30 13 06 07 2A 86 48 CE 3D 02 01 06 08 2A 81 |
| | 1C CF 55 01 82 2D |
| | Comments: Point compressed subjectPublicKey |
+-------+-----------------------------------------------------------+
Figure 14: C509 Public Key Algorithms
9.10.1. Suitability of different public key algorithms for use within
IoT scenarios
The public key algorithms registry Section 9.10 specify a number of
algorithms, not all which are suitable for usage with constrained
devices. RSA requires large keys and large signature sizes compared
to elliptic curve cryptography (ECC), which together with resource-
efficient implementations of named elliptic curves (Montgomery,
Edwards and Weierstraß curves), make them suitable candidates for IoT
public key usage. These curves are represented by ids 1–11 and 24–28
in Section 9.10.
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9.11. COSE Header Parameters Registry
IANA is requested to assign the entries in Table 1 to the "COSE
Header Parameters" registry under the "CBOR Object Signing and
Encryption (COSE)" heading with this document as reference.
9.12. Media Type application/cose-c509
When the application/cose-c509 media type is used, the data is a
COSE_C509 structure. If the parameter "usage" is set to "chain",
this sequence indicates a certificate chain.
IANA has registered the following media type [RFC6838]:
Type name: application Subtype name: cose-c509 Required parameters:
N/A Optional parameters: usage
* Can be absent to provide no further information about the intended
meaning of the order in the CBOR sequence of certificates.
* Can be set to "chain" to indicate that the sequence of data items
is to be interpreted as a certificate chain.
Encoding considerations: binary
Security considerations: See the Security Considerations section of
[[this document]].
Interoperability considerations: N/A
Published specification: [[this document]]
Applications that use this media type: Applications that employ COSE
and use C509 as a certificate type.
Fragment identifier considerations: N/A
Additional information:
Deprecated alias names for this type: N/A
Magic number(s): N/A
File extension(s): N/A
Macintosh file type code(s): N/A
Person & email address to contact for further information:
iesg@ietf.org
Intended usage: COMMON
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Restrictions on usage: N/A
Author: COSE WG
Change controller: IESG
9.13. TLS Certificate Types Registry
This document registers the following entry in the "TLS Certificate
Types" registry under the "Transport Layer Security (TLS) Extensions"
heading. The new certificate type can be used with additional TLS
certificate compression [RFC8879]. C509 is defined in the same way
as as X509, but uses a different value and instead of DER-encoded
X.509 certificate, opaque cert_data<1..2^24-1> contains a the CBOR
sequence ~C509Certificate (an unwrapped C509Certificate).
EDITOR'S NOTE: The TLS registrations should be discussed and approved
by the TLS WG at a later stage. When COSE WG has adopted work on
C509 certificates, it could perhaps be presented in the TLS WG. The
TLS WG might e.g. want a separate draft in the TLS WG.
+-------+------------------+-------------+--------------------------+
| Value | Name | Recommended | Comment |
+=======+==================+=============+==========================+
| TBD5 | C509 Certificate | Y | |
+-------+------------------+-------------+--------------------------+
9.14. CBOR Tags Registry
This document registers the following entries in the "CBOR Tags"
registry under the "Concise Binary Object Representation (CBOR) Tags"
heading.
+------+------------------------------------------------------------+
| Tag | X.509 Public Key Algorithms |
+======+============================================================+
| TDB6 | Data Item: COSE_C509 |
| | Semantics: An ordered chain of C509 certificates |
| | Reference: This document |
+------+------------------------------------------------------------+
10. References
10.1. Normative References
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[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119,
DOI 10.17487/RFC2119, March 1997,
<https://www.rfc-editor.org/info/rfc2119>.
[RFC4108] Housley, R., "Using Cryptographic Message Syntax (CMS) to
Protect Firmware Packages", RFC 4108,
DOI 10.17487/RFC4108, August 2005,
<https://www.rfc-editor.org/info/rfc4108>.
[RFC5280] Cooper, D., Santesson, S., Farrell, S., Boeyen, S.,
Housley, R., and W. Polk, "Internet X.509 Public Key
Infrastructure Certificate and Certificate Revocation List
(CRL) Profile", RFC 5280, DOI 10.17487/RFC5280, May 2008,
<https://www.rfc-editor.org/info/rfc5280>.
[RFC6838] Freed, N., Klensin, J., and T. Hansen, "Media Type
Specifications and Registration Procedures", BCP 13,
RFC 6838, DOI 10.17487/RFC6838, January 2013,
<https://www.rfc-editor.org/info/rfc6838>.
[RFC8174] Leiba, B., "Ambiguity of Uppercase vs Lowercase in RFC
2119 Key Words", BCP 14, RFC 8174, DOI 10.17487/RFC8174,
May 2017, <https://www.rfc-editor.org/info/rfc8174>.
[RFC8610] Birkholz, H., Vigano, C., and C. Bormann, "Concise Data
Definition Language (CDDL): A Notational Convention to
Express Concise Binary Object Representation (CBOR) and
JSON Data Structures", RFC 8610, DOI 10.17487/RFC8610,
June 2019, <https://www.rfc-editor.org/info/rfc8610>.
[RFC8742] Bormann, C., "Concise Binary Object Representation (CBOR)
Sequences", RFC 8742, DOI 10.17487/RFC8742, February 2020,
<https://www.rfc-editor.org/info/rfc8742>.
[RFC8949] Bormann, C. and P. Hoffman, "Concise Binary Object
Representation (CBOR)", STD 94, RFC 8949,
DOI 10.17487/RFC8949, December 2020,
<https://www.rfc-editor.org/info/rfc8949>.
[RFC9052] Schaad, J., "CBOR Object Signing and Encryption (COSE):
Structures and Process", STD 96, RFC 9052,
DOI 10.17487/RFC9052, August 2022,
<https://www.rfc-editor.org/info/rfc9052>.
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[RFC9090] Bormann, C., "Concise Binary Object Representation (CBOR)
Tags for Object Identifiers", RFC 9090,
DOI 10.17487/RFC9090, July 2021,
<https://www.rfc-editor.org/info/rfc9090>.
[RFC9360] Schaad, J., "CBOR Object Signing and Encryption (COSE):
Header Parameters for Carrying and Referencing X.509
Certificates", RFC 9360, DOI 10.17487/RFC9360, February
2023, <https://www.rfc-editor.org/info/rfc9360>.
[SECG] "Elliptic Curve Cryptography, Standards for Efficient
Cryptography Group, ver. 2", 2009,
<https://secg.org/sec1-v2.pdf>.
10.2. Informative References
[CAB-Code] CA/Browser Forum, "CA/Browser Forum, "Baseline
Requirements for the Issuance and Management of Publicly-
Trusted Code Signing Certificates Version 2.3"", May 2021,
<https://cabforum.org/baseline-requirements-code-
signing/>.
[CAB-TLS] CA/Browser Forum, "CA/Browser Forum, "Baseline
Requirements for the Issuance and Management of Publicly-
Trusted Certificates Version 1.7.6"", June 2021,
<https://cabforum.org/baseline-requirements-documents/>.
[CborMe] Bormann, C., "CBOR Playground", May 2018,
<http://cbor.me/>.
[GSMA-eUICC]
GSMA, "GSMA eUICC PKI Certificate Policy Version 2.1",
February 2021, <https://www.gsma.com/esim/wp-
content/uploads/2021/02/SGP.14-v2.1.pdf>.
[I-D.ietf-lake-edhoc]
Selander, G., Mattsson, J. P., and F. Palombini,
"Ephemeral Diffie-Hellman Over COSE (EDHOC)", Work in
Progress, Internet-Draft, draft-ietf-lake-edhoc-22, 25
August 2023, <https://datatracker.ietf.org/doc/html/draft-
ietf-lake-edhoc-22>.
[I-D.ietf-tls-ctls]
Rescorla, E., Barnes, R., Tschofenig, H., and B. M.
Schwartz, "Compact TLS 1.3", Work in Progress, Internet-
Draft, draft-ietf-tls-ctls-08, 13 March 2023,
<https://datatracker.ietf.org/doc/html/draft-ietf-tls-
ctls-08>.
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[I-D.ietf-uta-tls13-iot-profile]
Tschofenig, H. and T. Fossati, "TLS/DTLS 1.3 Profiles for
the Internet of Things", Work in Progress, Internet-Draft,
draft-ietf-uta-tls13-iot-profile-07, 14 September 2023,
<https://datatracker.ietf.org/doc/html/draft-ietf-uta-
tls13-iot-profile-07>.
[IEEE-802.1AR]
Institute of Electrical and Electronics Engineers, "IEEE
Standard for Local and metropolitan area networks–Secure
Device Identity", IEEE Standard 802.1AR-2018 , August
2018,
<https://standards.ieee.org/standard/802_1AR-2018.html>.
[RFC2985] Nystrom, M. and B. Kaliski, "PKCS #9: Selected Object
Classes and Attribute Types Version 2.0", RFC 2985,
DOI 10.17487/RFC2985, November 2000,
<https://www.rfc-editor.org/info/rfc2985>.
[RFC2986] Nystrom, M. and B. Kaliski, "PKCS #10: Certification
Request Syntax Specification Version 1.7", RFC 2986,
DOI 10.17487/RFC2986, November 2000,
<https://www.rfc-editor.org/info/rfc2986>.
[RFC6487] Huston, G., Michaelson, G., and R. Loomans, "A Profile for
X.509 PKIX Resource Certificates", RFC 6487,
DOI 10.17487/RFC6487, February 2012,
<https://www.rfc-editor.org/info/rfc6487>.
[RFC6955] Schaad, J. and H. Prafullchandra, "Diffie-Hellman Proof-
of-Possession Algorithms", RFC 6955, DOI 10.17487/RFC6955,
May 2013, <https://www.rfc-editor.org/info/rfc6955>.
[RFC7228] Bormann, C., Ersue, M., and A. Keranen, "Terminology for
Constrained-Node Networks", RFC 7228,
DOI 10.17487/RFC7228, May 2014,
<https://www.rfc-editor.org/info/rfc7228>.
[RFC7925] Tschofenig, H., Ed. and T. Fossati, "Transport Layer
Security (TLS) / Datagram Transport Layer Security (DTLS)
Profiles for the Internet of Things", RFC 7925,
DOI 10.17487/RFC7925, July 2016,
<https://www.rfc-editor.org/info/rfc7925>.
[RFC7932] Alakuijala, J. and Z. Szabadka, "Brotli Compressed Data
Format", RFC 7932, DOI 10.17487/RFC7932, July 2016,
<https://www.rfc-editor.org/info/rfc7932>.
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[RFC8446] Rescorla, E., "The Transport Layer Security (TLS) Protocol
Version 1.3", RFC 8446, DOI 10.17487/RFC8446, August 2018,
<https://www.rfc-editor.org/info/rfc8446>.
[RFC8603] Jenkins, M. and L. Zieglar, "Commercial National Security
Algorithm (CNSA) Suite Certificate and Certificate
Revocation List (CRL) Profile", RFC 8603,
DOI 10.17487/RFC8603, May 2019,
<https://www.rfc-editor.org/info/rfc8603>.
[RFC8879] Ghedini, A. and V. Vasiliev, "TLS Certificate
Compression", RFC 8879, DOI 10.17487/RFC8879, December
2020, <https://www.rfc-editor.org/info/rfc8879>.
[RFC9000] Iyengar, J., Ed. and M. Thomson, Ed., "QUIC: A UDP-Based
Multiplexed and Secure Transport", RFC 9000,
DOI 10.17487/RFC9000, May 2021,
<https://www.rfc-editor.org/info/rfc9000>.
[RFC9147] Rescorla, E., Tschofenig, H., and N. Modadugu, "The
Datagram Transport Layer Security (DTLS) Protocol Version
1.3", RFC 9147, DOI 10.17487/RFC9147, April 2022,
<https://www.rfc-editor.org/info/rfc9147>.
[RFC9148] van der Stok, P., Kampanakis, P., Richardson, M., and S.
Raza, "EST-coaps: Enrollment over Secure Transport with
the Secure Constrained Application Protocol", RFC 9148,
DOI 10.17487/RFC9148, April 2022,
<https://www.rfc-editor.org/info/rfc9148>.
[RFC9190] Preuß Mattsson, J. and M. Sethi, "EAP-TLS 1.3: Using the
Extensible Authentication Protocol with TLS 1.3",
RFC 9190, DOI 10.17487/RFC9190, February 2022,
<https://www.rfc-editor.org/info/rfc9190>.
[RFC9191] Sethi, M., Preuß Mattsson, J., and S. Turner, "Handling
Large Certificates and Long Certificate Chains in TLS-
Based EAP Methods", RFC 9191, DOI 10.17487/RFC9191,
February 2022, <https://www.rfc-editor.org/info/rfc9191>.
[X.509-IoT]
Forsby, F., Furuhed, M., Papadimitratos, P., and S. Raza,
"Lightweight X.509 Digital Certificates for the Internet
of Things.", Springer, Cham. Lecture Notes of the
Institute for Computer Sciences, Social Informatics and
Telecommunications Engineering, vol 242., July 2018,
<https://doi.org/10.1007/978-3-319-93797-7_14>.
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Appendix A. Example C509 Certificates
A.1. Example RFC 7925 profiled X.509 Certificate
Example of [RFC7925] profiled X.509 certificate parsed with OpenSSL.
Certificate:
Data:
Version: 3 (0x2)
Serial Number: 128269 (0x1f50d)
Signature Algorithm: ecdsa-with-SHA256
Issuer: CN=RFC test CA
Validity
Not Before: Jan 1 00:00:00 2023 GMT
Not After : Jan 1 00:00:00 2026 GMT
Subject: CN=01-23-45-FF-FE-67-89-AB
Subject Public Key Info:
Public Key Algorithm: id-ecPublicKey
Public-Key: (256 bit)
pub:
04:b1:21:6a:b9:6e:5b:3b:33:40:f5:bd:f0:2e:69:
3f:16:21:3a:04:52:5e:d4:44:50:b1:01:9c:2d:fd:
38:38:ab:ac:4e:14:d8:6c:09:83:ed:5e:9e:ef:24:
48:c6:86:1c:c4:06:54:71:77:e6:02:60:30:d0:51:
f7:79:2a:c2:06
ASN1 OID: prime256v1
NIST CURVE: P-256
X509v3 extensions:
X509v3 Key Usage:
Digital Signature
Signature Algorithm: ecdsa-with-SHA256
30:46:02:21:00:d4:32:0b:1d:68:49:e3:09:21:9d:30:03:7e:
13:81:66:f2:50:82:47:dd:da:e7:6c:ce:ea:55:05:3c:10:8e:
90:02:21:00:d5:51:f6:d6:01:06:f1:ab:b4:84:cf:be:62:56:
c1:78:e4:ac:33:14:ea:19:19:1e:8b:60:7d:a5:ae:3b:da:16
The DER encoding of the above certificate is 316 bytes.
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30 82 01 38 30 81 de a0 03 02 01 02 02 03 01 f5 0d 30 0a 06 08 2a 86
48 ce 3d 04 03 02 30 16 31 14 30 12 06 03 55 04 03 0c 0b 52 46 43 20
74 65 73 74 20 43 41 30 1e 17 0d 32 33 30 31 30 31 30 30 30 30 30 30
5a 17 0d 32 36 30 31 30 31 30 30 30 30 30 30 5a 30 22 31 20 30 1e 06
03 55 04 03 0c 17 30 31 2d 32 33 2d 34 35 2d 46 46 2d 46 45 2d 36 37
2d 38 39 2d 41 42 30 59 30 13 06 07 2a 86 48 ce 3d 02 01 06 08 2a 86
48 ce 3d 03 01 07 03 42 00 04 b1 21 6a b9 6e 5b 3b 33 40 f5 bd f0 2e
69 3f 16 21 3a 04 52 5e d4 44 50 b1 01 9c 2d fd 38 38 ab ac 4e 14 d8
6c 09 83 ed 5e 9e ef 24 48 c6 86 1c c4 06 54 71 77 e6 02 60 30 d0 51
f7 79 2a c2 06 a3 0f 30 0d 30 0b 06 03 55 1d 0f 04 04 03 02 07 80 30
0a 06 08 2a 86 48 ce 3d 04 03 02 03 49 00 30 46 02 21 00 d4 32 0b 1d
68 49 e3 09 21 9d 30 03 7e 13 81 66 f2 50 82 47 dd da e7 6c ce ea 55
05 3c 10 8e 90 02 21 00 d5 51 f6 d6 01 06 f1 ab b4 84 cf be 62 56 c1
78 e4 ac 33 14 ea 19 19 1e 8b 60 7d a5 ae 3b da 16
A.1.1. Example C509 Certificate Encoding
The CBOR encoding (~C509Certificate) of the same X.509 certificate is
shown below in CBOR diagnostic format.
/This defines a CBOR Sequence (RFC 8742):/
1, / version and certificate type /
h'01f50d', / serialNumber /
"RFC test CA", / issuer /
1672531200, / notBefore /
1767225600, / notAfter /
h'010123456789AB', / subject, EUI-64 /
1, / subjectPublicKeyAlgorithm /
h'02B1216AB96E5B3B3340F5BDF02E693F16213A04525ED44450
B1019C2DFD3838AB',
1, / single extension:
non-critical keyUsage
digitalSignature /
0, / signatureAlgorithm /
h'D4320B1D6849E309219D30037E138166F2508247DDDAE76CCE
EA55053C108E90D551F6D60106F1ABB484CFBE6256C178E4AC
3314EA19191E8B607DA5AE3BDA16'
The size of the CBOR encoding (CBOR sequence) is 139 bytes. The
point compressed public key is represented as described in
Section 3.2.1.
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01
43 01 F5 0D
6B 52 46 43 20 74 65 73 74 20 43 41
1A 63 B0 CD 00
1A 69 55 B9 00
47 01 01 23 45 67 89 AB
01
58 21 02 B1 21 6A B9 6E 5B 3B 33 40 F5 BD F0 2E 69 3F 16 21 3A 04 52
5E D4 44 50 B1 01 9C 2D FD 38 38 AB
01
00
58 40 D4 32 0B 1D 68 49 E3 09 21 9D 30 03 7E 13 81 66 F2 50 82 47 DD
DA E7 6C CE EA 55 05 3C 10 8E 90 D5 51 F6 D6 01 06 F1 AB B4 84 CF BE
62 56 C1 78 E4 AC 33 14 EA 19 19 1E 8B 60 7D A5 AE 3B DA 16
A.1.2. Example: Natively Signed C509 Certificate
The corresponding natively signed C509 certificate in CBOR diagnostic
format is identical, except for c509CertificateType, encoding of
point compression (see Section 3.2.1), and signatureValue.
/This defines a CBOR Sequence (RFC 8742):/
0,
h'01f50d',
"RFC test CA",
1672531200,
1767225600,
h'010123456789AB',
1,
h'02B1216AB96E5B3B3340F5BDF02E693F16213A04525ED44450
B1019C2DFD3838AB',
1,
0,
h'6FC903015259A38C0800A3D0B2969CA21977E8ED6EC344964D
4E1C6B37C8FB541274C3BB81B2F53073C5F101A5AC2A928865
83B6A2679B6E682D2A26945ED0B2'
The size of the CBOR encoding (CBOR sequence) is 139 bytes.
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00
43 01 F5 0D
6B 52 46 43 20 74 65 73 74 20 43 41
1A 63 B0 CD 00
1A 69 55 B9 00
47 01 01 23 45 67 89 AB
01
58 21 02 B1 21 6A B9 6E 5B 3B 33 40 F5 BD F0 2E 69 3F 16 21 3A 04 52
5E D4 44 50 B1 01 9C 2D FD 38 38 AB
01
00
58 40 6F C9 03 01 52 59 A3 8C 08 00 A3 D0 B2 96 9C A2 19 77 E8 ED 6E
C3 44 96 4D 4E 1C 6B 37 C8 FB 54 12 74 C3 BB 81 B2 F5 30 73 C5 F1 01
A5 AC 2A 92 88 65 83 B6 A2 67 9B 6E 68 2D 2A 26 94 5E D0 B2
A.1.3. C509 for Diffie-Hellman keys
The two previous examples illustrate the common key usage
digitalSignature. A C509 certificate for a public Diffie-Hellman key
would instead have key usage keyAgreement encoded according to
Section 3.3 (in this case of single extension encoded as integer 16
instead of 1 for digital signature) but otherwise identical in
format.
A.1.4. Example: Additional Keys for the Example Certificates
Below are the issuer key pair and the subject private key belonging
to the above example certificates. The private keys are encoded as
in COSE [RFC9052]. These issuer key pair can be used to sign or
verify the example certificates and the subject private key allows
the example certificates to be used in test vectors for other
protocols like EDHOC.
issuerPublicKeyAlgorithm :
1 (EC Public Key (Weierstraß) with secp256r1)
issuerPublicKey :
h'02AE4CDB01F614DEFC7121285FDC7F5C6D1D42C95647F061BA0080DF678867845E'
issuerPrivateKey :
h'DC66B3415456D649429B53223DF7532B942D6B0E0842C30BCA4C0ACF91547BB2'
subjectPrivateKey :
h'D718111F3F9BD91B92FF6877F386BDBFCEA7154268FD7F2FB56EE17D99EA16D4'
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A.2. Example IEEE 802.1AR profiled X.509 Certificate
EDITOR'S NOTE: Need good example, or remove section
One example of an IEEE 802.1AR profiled X.509 certificate (IDevID) is
provided in [RFC9148]. The DER encoding is given in the second
example in Appendix A.2, and the plain text is in the second example
of Appendix C.2. The X509v3 Subject Alternative Name is of type
OtherName (see [RFC5280]), with type-id = id-on-hardwareModuleName
(see [RFC4108]) consisting of hardware type OID and hardware serial
number of the device, in that example being 1.3.6.1.4.1.6715.1.10 and
01020304, respectively.
A.2.1. Example C509 Certificate Encoding
A.3. Example CAB Baseline ECDSA HTTPS X.509 Certificate
The www.ietf.org HTTPS server replies with a certificate message with
2 certificates. The DER encoding of the first certificate is 1209
bytes.
30 82 04 b5 30 82 04 5a a0 03 02 01 02 02 10 04 7f a1 e3 19 28 ee 40
3b a0 b8 3a 39 56 73 fc 30 0a 06 08 2a 86 48 ce 3d 04 03 02 30 4a 31
0b 30 09 06 03 55 04 06 13 02 55 53 31 19 30 17 06 03 55 04 0a 13 10
43 6c 6f 75 64 66 6c 61 72 65 2c 20 49 6e 63 2e 31 20 30 1e 06 03 55
04 03 13 17 43 6c 6f 75 64 66 6c 61 72 65 20 49 6e 63 20 45 43 43 20
43 41 2d 33 30 1e 17 0d 32 30 30 37 32 39 30 30 30 30 30 30 5a 17 0d
32 31 30 37 32 39 31 32 30 30 30 30 5a 30 6d 31 0b 30 09 06 03 55 04
06 13 02 55 53 31 0b 30 09 06 03 55 04 08 13 02 43 41 31 16 30 14 06
03 55 04 07 13 0d 53 61 6e 20 46 72 61 6e 63 69 73 63 6f 31 19 30 17
06 03 55 04 0a 13 10 43 6c 6f 75 64 66 6c 61 72 65 2c 20 49 6e 63 2e
31 1e 30 1c 06 03 55 04 03 13 15 73 6e 69 2e 63 6c 6f 75 64 66 6c 61
72 65 73 73 6c 2e 63 6f 6d 30 59 30 13 06 07 2a 86 48 ce 3d 02 01 06
08 2a 86 48 ce 3d 03 01 07 03 42 00 04 96 3e cd d8 4d cd 1b 93 a1 cf
43 2d 1a 72 17 d6 c6 3b de 33 55 a0 2f 8c fb 5a d8 99 4c d4 4e 20 5f
15 f6 e3 d2 3b 38 2b a6 49 9b b1 7f 34 1f a5 92 fa 21 86 1f 16 d3 12
06 63 24 05 fd 70 42 bd a3 82 02 fd 30 82 02 f9 30 1f 06 03 55 1d 23
04 18 30 16 80 14 a5 ce 37 ea eb b0 75 0e 94 67 88 b4 45 fa d9 24 10
87 96 1f 30 1d 06 03 55 1d 0e 04 16 04 14 cc 0b 50 e7 d8 37 db f2 43
f3 85 3d 48 60 f5 3b 39 be 9b 2a 30 2e 06 03 55 1d 11 04 27 30 25 82
15 73 6e 69 2e 63 6c 6f 75 64 66 6c 61 72 65 73 73 6c 2e 63 6f 6d 82
0c 77 77 77 2e 69 65 74 66 2e 6f 72 67 30 0e 06 03 55 1d 0f 01 01 ff
04 04 03 02 07 80 30 1d 06 03 55 1d 25 04 16 30 14 06 08 2b 06 01 05
05 07 03 01 06 08 2b 06 01 05 05 07 03 02 30 7b 06 03 55 1d 1f 04 74
30 72 30 37 a0 35 a0 33 86 31 68 74 74 70 3a 2f 2f 63 72 6c 33 2e 64
69 67 69 63 65 72 74 2e 63 6f 6d 2f 43 6c 6f 75 64 66 6c 61 72 65 49
6e 63 45 43 43 43 41 2d 33 2e 63 72 6c 30 37 a0 35 a0 33 86 31 68 74
74 70 3a 2f 2f 63 72 6c 34 2e 64 69 67 69 63 65 72 74 2e 63 6f 6d 2f
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43 6c 6f 75 64 66 6c 61 72 65 49 6e 63 45 43 43 43 41 2d 33 2e 63 72
6c 30 4c 06 03 55 1d 20 04 45 30 43 30 37 06 09 60 86 48 01 86 fd 6c
01 01 30 2a 30 28 06 08 2b 06 01 05 05 07 02 01 16 1c 68 74 74 70 73
3a 2f 2f 77 77 77 2e 64 69 67 69 63 65 72 74 2e 63 6f 6d 2f 43 50 53
30 08 06 06 67 81 0c 01 02 02 30 76 06 08 2b 06 01 05 05 07 01 01 04
6a 30 68 30 24 06 08 2b 06 01 05 05 07 30 01 86 18 68 74 74 70 3a 2f
2f 6f 63 73 70 2e 64 69 67 69 63 65 72 74 2e 63 6f 6d 30 40 06 08 2b
06 01 05 05 07 30 02 86 34 68 74 74 70 3a 2f 2f 63 61 63 65 72 74 73
2e 64 69 67 69 63 65 72 74 2e 63 6f 6d 2f 43 6c 6f 75 64 66 6c 61 72
65 49 6e 63 45 43 43 43 41 2d 33 2e 63 72 74 30 0c 06 03 55 1d 13 01
01 ff 04 02 30 00 30 82 01 05 06 0a 2b 06 01 04 01 d6 79 02 04 02 04
81 f6 04 81 f3 00 f1 00 76 00 f6 5c 94 2f d1 77 30 22 14 54 18 08 30
94 56 8e e3 4d 13 19 33 bf df 0c 2f 20 0b cc 4e f1 64 e3 00 00 01 73
9c 83 5f 8e 00 00 04 03 00 47 30 45 02 21 00 f8 d1 b4 a9 3d 2f 0d 4c
41 76 df b4 88 bc c7 3b 86 44 3d 7d e0 0e 6a c8 17 4d 89 48 a8 84 36
68 02 20 29 ff 5a 34 06 8a 24 0c 69 50 27 88 e8 ee 25 ab 7e d2 cb cf
68 6e ce 7b 5f 96 b4 31 a9 07 02 fa 00 77 00 5c dc 43 92 fe e6 ab 45
44 b1 5e 9a d4 56 e6 10 37 fb d5 fa 47 dc a1 73 94 b2 5e e6 f6 c7 0e
ca 00 00 01 73 9c 83 5f be 00 00 04 03 00 48 30 46 02 21 00 e8 91 c1
97 bf b0 e3 d3 0c b6 ce e6 0d 94 c3 c7 5f d1 17 53 36 93 11 08 d8 98
12 d4 d2 9d 81 d0 02 21 00 a1 59 d1 6c 46 47 d1 48 37 57 fc d6 ce 4e
75 ec 7b 5e f6 57 ef e0 28 f8 e5 cc 47 92 68 2d ac 43 30 0a 06 08 2a
86 48 ce 3d 04 03 02 03 49 00 30 46 02 21 00 bd 63 cf 4f 7e 5c fe 6c
29 38 5e a7 1c fb fc 1e 3f 7b 1c d0 72 51 a2 21 f7 77 69 c0 f4 71 df
ea 02 21 00 b5 c0 6c c4 58 54 fa 30 b2 82 88 b1 d3 bb 9a 66 61 ed 50
31 72 5b 1a 82 02 e0 da 5b 59 f9 54 02
A.3.1. Example C509 Certificate Encoding
The CBOR encoding (~C509Certificate) of the first X.509 certificate
is shown below in CBOR diagnostic format.
/This defines a CBOR Sequence (RFC 8742):/
1,
h'047FA1E31928EE403BA0B83A395673FC',
[
-4, "US",
-8, "Cloudflare, Inc.",
-1, "Cloudflare Inc ECC CA-3"
],
1595980800,
1627560000,
[
-4, "US",
-6, "CA",
-5, "San Francisco",
-8, "Cloudflare, Inc.",
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-1, "sni.cloudflaressl.com"
],
1,
h'03963ECDD84DCD1B93A1CF432D1A7217D6C63BDE3355A02F8CFB5AD8994CD44E20',
[
7, h'A5CE37EAEBB0750E946788B445FAD9241087961F',
1, h'CC0B50E7D837DBF243F3853D4860F53B39BE9B2A',
3, [2, "sni.cloudflaressl.com", 2, "www.ietf.org"],
-2, 1,
8, [1, 2],
5, ["http://crl3.digicert.com/CloudflareIncECCCA-3.crl",
"http://crl4.digicert.com/CloudflareIncECCCA-3.crl"],
6, [h'6086480186FD6C0101', [1, "https://www.digicert.com/CPS"], 2],
9, [1, "http://ocsp.digicert.com",
2, "http://cacerts.digicert.com/CloudflareIncECCCA-3.crt"],
-4, -2,
10, [
h'F65C942FD1773022145418083094568EE34D131933BFDF0C2F200BCC4EF164E3',
77922190,
0,
h'F8D1B4A93D2F0D4C4176DFB488BCC73B86443D7DE00E6AC8174D8948A8843668
29FF5A34068A240C69502788E8EE25AB7ED2CBCF686ECE7B5F96B431A90702FA',
h'5CDC4392FEE6AB4544B15E9AD456E61037FBD5FA47DCA17394B25EE6F6C70ECA',
77922238,
0,
h'E891C197BFB0E3D30CB6CEE60D94C3C75FD1175336931108D89812D4D29D81D0
A159D16C4647D1483757FCD6CE4E75EC7B5EF657EFE028F8E5CC4792682DAC43'
]
],
0,
h'BD63CF4F7E5CFE6C29385EA71CFBFC1E3F7B1CD07251A221F77769C0F471DFEA
B5C06CC45854FA30B28288B1D3BB9A6661ED5031725B1A8202E0DA5B59F95402'
The size of the CBOR encoding (CBOR sequence) is 783 bytes.
A.4. Example CAB Baseline RSA HTTPS X.509 Certificate
The tools.ietf.org HTTPS server replies with a certificate message
with 4 certificates. The DER encoding of the first certificate is
1647 bytes.
30 82 06 6b 30 82 05 53 a0 03 02 01 02 02 09 00 a6 a5 5c 87 0e 39 b4
0e 30 0d 06 09 2a 86 48 86 f7 0d 01 01 0b 05 00 30 81 c6 31 0b 30 09
06 03 55 04 06 13 02 55 53 31 10 30 0e 06 03 55 04 08 13 07 41 72 69
7a 6f 6e 61 31 13 30 11 06 03 55 04 07 13 0a 53 63 6f 74 74 73 64 61
6c 65 31 25 30 23 06 03 55 04 0a 13 1c 53 74 61 72 66 69 65 6c 64 20
54 65 63 68 6e 6f 6c 6f 67 69 65 73 2c 20 49 6e 63 2e 31 33 30 31 06
03 55 04 0b 13 2a 68 74 74 70 3a 2f 2f 63 65 72 74 73 2e 73 74 61 72
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66 69 65 6c 64 74 65 63 68 2e 63 6f 6d 2f 72 65 70 6f 73 69 74 6f 72
79 2f 31 34 30 32 06 03 55 04 03 13 2b 53 74 61 72 66 69 65 6c 64 20
53 65 63 75 72 65 20 43 65 72 74 69 66 69 63 61 74 65 20 41 75 74 68
6f 72 69 74 79 20 2d 20 47 32 30 1e 17 0d 32 30 31 30 30 31 31 39 33
38 33 36 5a 17 0d 32 31 31 31 30 32 31 39 33 38 33 36 5a 30 3e 31 21
30 1f 06 03 55 04 0b 13 18 44 6f 6d 61 69 6e 20 43 6f 6e 74 72 6f 6c
20 56 61 6c 69 64 61 74 65 64 31 19 30 17 06 03 55 04 03 0c 10 2a 2e
74 6f 6f 6c 73 2e 69 65 74 66 2e 6f 72 67 30 82 01 22 30 0d 06 09 2a
86 48 86 f7 0d 01 01 01 05 00 03 82 01 0f 00 30 82 01 0a 02 82 01 01
00 b1 e1 37 e8 eb 82 d6 89 fa db f5 c2 4b 77 f0 2c 4a de 72 6e 3e 13
60 d1 a8 66 1e c4 ad 3d 32 60 e5 f0 99 b5 f4 7a 7a 48 55 21 ee 0e 39
12 f9 ce 0d ca f5 69 61 c7 04 ed 6e 0f 1d 3b 1e 50 88 79 3a 0e 31 41
16 f1 b1 02 64 68 a5 cd f5 4a 0a ca 99 96 35 08 c3 7e 27 5d d0 a9 cf
f3 e7 28 af 37 d8 b6 7b dd f3 7e ae 6e 97 7f f7 ca 69 4e cc d0 06 df
5d 27 9b 3b 12 e7 e6 fe 08 6b 52 7b 82 11 7c 72 b3 46 eb c1 e8 78 b8
0f cb e1 eb bd 06 44 58 dc 83 50 b2 a0 62 5b dc 81 b8 36 e3 9e 7c 79
b2 a9 53 8a e0 0b c9 4a 2a 13 39 31 13 bd 2c cf a8 70 cf 8c 8d 3d 01
a3 88 ae 12 00 36 1d 1e 24 2b dd 79 d8 53 01 26 ed 28 4f c9 86 94 83
4e c8 e1 14 2e 85 b3 af d4 6e dd 69 46 af 41 25 0e 7a ad 8b f2 92 ca
79 d9 7b 32 4f f7 77 e8 f9 b4 4f 23 5c d4 5c 03 ae d8 ab 3a ca 13 5f
5d 5d 5d a1 02 03 01 00 01 a3 82 02 e1 30 82 02 dd 30 0c 06 03 55 1d
13 01 01 ff 04 02 30 00 30 1d 06 03 55 1d 25 04 16 30 14 06 08 2b 06
01 05 05 07 03 01 06 08 2b 06 01 05 05 07 03 02 30 0e 06 03 55 1d 0f
01 01 ff 04 04 03 02 05 a0 30 3d 06 03 55 1d 1f 04 36 30 34 30 32 a0
30 a0 2e 86 2c 68 74 74 70 3a 2f 2f 63 72 6c 2e 73 74 61 72 66 69 65
6c 64 74 65 63 68 2e 63 6f 6d 2f 73 66 69 67 32 73 31 2d 32 34 32 2e
63 72 6c 30 63 06 03 55 1d 20 04 5c 30 5a 30 4e 06 0b 60 86 48 01 86
fd 6e 01 07 17 01 30 3f 30 3d 06 08 2b 06 01 05 05 07 02 01 16 31 68
74 74 70 3a 2f 2f 63 65 72 74 69 66 69 63 61 74 65 73 2e 73 74 61 72
66 69 65 6c 64 74 65 63 68 2e 63 6f 6d 2f 72 65 70 6f 73 69 74 6f 72
79 2f 30 08 06 06 67 81 0c 01 02 01 30 81 82 06 08 2b 06 01 05 05 07
01 01 04 76 30 74 30 2a 06 08 2b 06 01 05 05 07 30 01 86 1e 68 74 74
70 3a 2f 2f 6f 63 73 70 2e 73 74 61 72 66 69 65 6c 64 74 65 63 68 2e
63 6f 6d 2f 30 46 06 08 2b 06 01 05 05 07 30 02 86 3a 68 74 74 70 3a
2f 2f 63 65 72 74 69 66 69 63 61 74 65 73 2e 73 74 61 72 66 69 65 6c
64 74 65 63 68 2e 63 6f 6d 2f 72 65 70 6f 73 69 74 6f 72 79 2f 73 66
69 67 32 2e 63 72 74 30 1f 06 03 55 1d 23 04 18 30 16 80 14 25 45 81
68 50 26 38 3d 3b 2d 2c be cd 6a d9 b6 3d b3 66 63 30 2b 06 03 55 1d
11 04 24 30 22 82 10 2a 2e 74 6f 6f 6c 73 2e 69 65 74 66 2e 6f 72 67
82 0e 74 6f 6f 6c 73 2e 69 65 74 66 2e 6f 72 67 30 1d 06 03 55 1d 0e
04 16 04 14 ad 8a b4 1c 07 51 d7 92 89 07 b0 b7 84 62 2f 36 55 7a 5f
4d 30 82 01 06 06 0a 2b 06 01 04 01 d6 79 02 04 02 04 81 f7 04 81 f4
00 f2 00 77 00 f6 5c 94 2f d1 77 30 22 14 54 18 08 30 94 56 8e e3 4d
13 19 33 bf df 0c 2f 20 0b cc 4e f1 64 e3 00 00 01 74 e5 ac 71 13 00
00 04 03 00 48 30 46 02 21 00 8c f5 48 52 ce 56 35 43 39 11 cf 10 cd
b9 1f 52 b3 36 39 22 3a d1 38 a4 1d ec a6 fe de 1f e9 0f 02 21 00 bc
a2 25 43 66 c1 9a 26 91 c4 7a 00 b5 b6 53 ab bd 44 c2 f8 ba ae f4 d2
da f2 52 7c e6 45 49 95 00 77 00 5c dc 43 92 fe e6 ab 45 44 b1 5e 9a
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d4 56 e6 10 37 fb d5 fa 47 dc a1 73 94 b2 5e e6 f6 c7 0e ca 00 00 01
74 e5 ac 72 3c 00 00 04 03 00 48 30 46 02 21 00 a5 e0 90 6e 63 e9 1d
4f dd ef ff 03 52 b9 1e 50 89 60 07 56 4b 44 8a 38 28 f5 96 dc 6b 28
72 6d 02 21 00 fc 91 ea ed 02 16 88 66 05 4e e1 8a 2e 53 46 c4 cc 51
fe b3 fa 10 a9 1d 2e db f9 91 25 f8 6c e6 30 0d 06 09 2a 86 48 86 f7
0d 01 01 0b 05 00 03 82 01 01 00 14 04 3f a0 be d2 ee 3f a8 6e 3a 1f
78 8e a0 4c 35 53 0f 11 06 1f ff 60 a1 6d 0b 83 e9 d9 2a db b3 3f 9d
b3 d7 e0 59 4c 19 a8 e4 19 a5 0c a7 70 72 77 63 d5 fe 64 51 0a d2 7a
d6 50 a5 8a 92 38 ec cb 2f 0f 5a c0 64 58 4d 5c 06 b9 73 63 68 27 8b
89 34 dc 79 c7 1d 3a fd 34 5f 83 14 41 58 49 80 68 29 80 39 8a 86 72
69 cc 79 37 ce e3 97 f7 dc f3 95 88 ed 81 03 29 00 d2 a2 c7 ba ab d6
3a 8e ca 09 0b d9 fb 39 26 4b ff 03 d8 8e 2d 3f 6b 21 ca 8a 7d d8 5f
fb 94 ba 83 de 9c fc 15 8d 61 fa 67 2d b0 c7 db 3d 25 0a 41 4a 85 d3
7f 49 46 37 3c f4 b1 75 d0 52 f3 dd c7 66 f1 4b fd aa 00 ed bf e4 7e
ed 01 ec 7b e4 f6 46 fc 31 fd 72 fe 03 d2 f2 65 af 4d 7e e2 81 9b 7a
fd 30 3c f5 52 f4 05 34 a0 8a 3e 19 41 58 c8 a8 e0 51 71 84 09 15 ae
ec a5 77 75 fa 18 f7 d5 77 d5 31 cc c7 2d
A.4.1. Example C509 Certificate Encoding
The CBOR encoding (~C509Certificate) of the first X.509 certificate
is shown below in CBOR diagnostic format.
/This defines a CBOR Sequence (RFC 8742):/
1,
h'A6A55C870E39B40E',
[
-4, "US",
-6, "Arizona",
-5, "Scottsdale",
-8, "Starfield Technologies, Inc.",
-9, "http://certs.starfieldtech.com/repository/",
-1, "Starfield Secure Certificate Authority - G2"
],
1601581116,
1635881916,
[
-9, "Domain Control Validated",
1, "*.tools.ietf.org"
],
0,
h'B1E137E8EB82D689FADBF5C24B77F02C4ADE726E3E1360D1A8661EC4AD3D3260
E5F099B5F47A7A485521EE0E3912F9CE0DCAF56961C704ED6E0F1D3B1E508879
3A0E314116F1B1026468A5CDF54A0ACA99963508C37E275DD0A9CFF3E728AF37
D8B67BDDF37EAE6E977FF7CA694ECCD006DF5D279B3B12E7E6FE086B527B8211
7C72B346EBC1E878B80FCBE1EBBD064458DC8350B2A0625BDC81B836E39E7C79
B2A9538AE00BC94A2A13393113BD2CCFA870CF8C8D3D01A388AE1200361D1E24
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2BDD79D8530126ED284FC98694834EC8E1142E85B3AFD46EDD6946AF41250E7A
AD8BF292CA79D97B324FF777E8F9B44F235CD45C03AED8AB3ACA135F5D5D5DA1',
[
-4, -2,
8, [ 1, 2 ],
-2, 5,
5, ["http://crl.starfieldtech.com/sfig2s1-242.crl"],
6, [ h'6086480186fd6e01071701',
[1, "http://certificates.starfieldtech.com/repository/"], 1 ],
9, [ 1, "http://ocsp.starfieldtech.com/",
2, "http://certificates.starfieldtech.com/repository/sfig2.crt" ],
7, h'254581685026383D3B2D2CBECD6AD9B63DB36663',
3, [ 2, "*.tools.ietf.org", 2, "tools.ietf.org" ],
1, h'AD8AB41C0751D7928907B0B784622F36557A5F4D',
10, [
h'F65C942FD1773022145418083094568EE34D131933BFDF0C2F200BCC4EF164E3',
1715,
0,
h'8CF54852CE5635433911CF10CDB91F52B33639223AD138A41DECA6FEDE1FE90F
BCA2254366C19A2691C47A00B5B653ABBD44C2F8BAAEF4D2DAF2527CE6454995',
h'5CDC4392FEE6AB4544B15E9AD456E61037FBD5FA47DCA17394B25EE6F6C70ECA',
2012,
0,
h'A5E0906E63E91D4FDDEFFF0352B91E50896007564B448A3828F596DC6B28726D
FC91EAED02168866054EE18A2E5346C4CC51FEB3FA10A91D2EDBF99125F86CE6'
]
],
23,
h'14043FA0BED2EE3FA86E3A1F788EA04C35530F11061FFF60A16D0B83E9D92ADB
B33F9DB3D7E0594C19A8E419A50CA770727763D5FE64510AD27AD650A58A9238
ECCB2F0F5AC064584D5C06B9736368278B8934DC79C71D3AFD345F8314415849
80682980398A867269CC7937CEE397F7DCF39588ED81032900D2A2C7BAABD63A
8ECA090BD9FB39264BFF03D88E2D3F6B21CA8A7DD85FFB94BA83DE9CFC158D61
FA672DB0C7DB3D250A414A85D37F4946373CF4B175D052F3DDC766F14BFDAA00
EDBFE47EED01EC7BE4F646FC31FD72FE03D2F265AF4D7EE2819B7AFD303CF552
F40534A08A3E194158C8A8E05171840915AEECA57775FA18F7D577D531CCC72D'
The size of the CBOR encoding (CBOR sequence) is 1245 bytes.
Acknowledgments
The authors want to thank Henk Birkholz, Carsten Bormann, Russ
Housley, Olle Johansson, Benjamin Kaduk, Ilari Liusvaara, Laurence
Lundblade, Francesca Palombini, Thomas Peterson, Michael Richardson,
Stefan Santesson, Jim Schaad, Brian Sipos, Fraser Tweedale, and Rene
Struik for reviewing and commenting on intermediate versions of the
draft and helping with GitHub.
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Authors' Addresses
John Preuß Mattsson
Ericsson AB
Email: john.mattsson@ericsson.com
Göran Selander
Ericsson AB
Email: goran.selander@ericsson.com
Shahid Raza
RISE AB
Email: shahid.raza@ri.se
Joel Höglund
RISE AB
Email: joel.hoglund@ri.se
Martin Furuhed
Nexus Group
Email: martin.furuhed@nexusgroup.com
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